View source for Library of Congress

{{Short description|US Congress research library}}
{{About|the United States Library of Congress}}
{{Use American English|date = March 2019}}
{{Use mdy dates|date=October 2023}}
{{Infobox library
| name = Library of Congress
| library_logo = Library of Congress 2018 logo.svg
| image = LOC Main Reading Room Highsmith.jpg
| caption = Main reading room in the [[Thomas Jefferson Building]] at the Library of Congress
| location = 101 [[Independence Avenue (Washington, D.C.)|Independence Ave.]], S.E., Washington, D.C., U.S.
| coordinates = {{Coord|38|53|19|N|77|0|17|W|region:US-DC_type:landmark|display=inline,title}}
| mapframe = no
| established = {{start date and age|April 24, 1800}}
| num_branches = 
| collection_size = 173 million items{{Efn|The collection includes: 25 million catalogued books, 15.5 million other print items, 4.2 million recordings, 74.5 million manuscripts, 5.6 million maps, and 8.2 million sheet music pieces.<ref name="Year 2020 at a Glance">{{cite web |title=Year 2020 at a Glance |url=https://www.loc.gov/about/general-information/ |date=2020 |publisher=Library of Congress |access-date=November 5, 2021 |archive-date=February 23, 2021 |archive-url=https://web.archive.org/web/20210223101833/https://www.loc.gov/about/general-information/ |url-status=live }}</ref>}}
| annual_circulation = Onsite use only
| pop_served = [[United States Congress|Congress]], citizens, and international visitors
| budget = $802.128&nbsp;million<ref name="2017annualreport">{{cite web |url=https://www.loc.gov/static/portals/about/reports-and-budgets/documents/annual-reports/fy2021.pdf |title=2021 Annual Report of the Librarian of Congress |publisher=Library of Congress |access-date=December 2, 2022 |archive-date=February 3, 2023 |archive-url=https://web.archive.org/web/20230203043127/https://www.loc.gov/static/portals/about/reports-and-budgets/documents/annual-reports/fy2021.pdf |url-status=live }}</ref>
| director = Robert Newlen, Acting
| num_employees = 3,105<ref name="2017annualreport"/>
| website = {{official URL}}
}}

The '''Library of Congress''' ('''LOC''') is a [[research library]] in Washington, D.C., serving as the library and research service for the [[United States Congress]] and the ''de facto'' [[national library]] of the United States.<ref name="Encyclopedia Britannica: Library of Congress"/> It also administers [[Copyright law of the United States|copyright law]] through the [[United States Copyright Office]], and it houses the [[Congressional Research Service]].

Founded in 1800, the Library of Congress is the oldest [[Cultural policy of the United States|federal cultural institution]] in the United States.<ref name="Fascinating Facts">{{cite web |url=https://www.loc.gov/about/fascinating-facts/ |title=Fascinating Facts |publisher=Library of Congress |access-date=April 25, 2018 |archive-date=April 5, 2020 |archive-url=https://web.archive.org/web/20200405144735/https://www.loc.gov/about/fascinating-facts/ |url-status=live }}</ref> It is housed in three buildings on [[Capitol Hill]], adjacent to the [[United States Capitol]], along with the [[National Audio-Visual Conservation Center]] in [[Culpeper, Virginia]], and additional storage facilities at [[Fort Meade|Fort George G. Meade]] and Cabin Branch in [[Hyattsville, Maryland]].<ref name="GeneralInfo">{{cite web |url=https://www.loc.gov/about/general-information/ |title=General Information |publisher=Library of Congress |access-date=January 28, 2023 |archive-date=February 23, 2021 |archive-url=https://web.archive.org/web/20210223101833/https://www.loc.gov/about/general-information/ |url-status=live }}</ref> The library's functions are overseen by the [[librarian of Congress]], and its buildings are maintained by the [[architect of the Capitol]]. The LOC is one of the [[List of largest libraries|largest libraries in the world]],<ref name="Encyclopedia Britannica: Library of Congress">{{cite web |title=Library of Congress |url=https://www.britannica.com/topic/Library-of-Congress |website=Encyclopædia Britannica |access-date=September 3, 2017 |archive-date=April 5, 2020 |archive-url=https://web.archive.org/web/20200405144736/https://www.britannica.com/topic/Library-of-Congress |url-status=live }}</ref><ref name="FFStats">{{cite web |title=Fascinating Facts – Statistics |url=https://www.loc.gov/about/fascinating-facts/ |publisher=Library of Congress |access-date=February 16, 2017 |archive-date=April 5, 2020 |archive-url=https://web.archive.org/web/20200405144735/https://www.loc.gov/about/fascinating-facts/ |url-status=live }}</ref> containing approximately 173 million items and employing over 3,000 staff. Its collections are "universal, not limited by subject, format, or national boundary, and include research materials from all parts of the world and in more than 470 languages".<ref name="Fascinating Facts" />

When [[Congress of the United States|Congress]] moved to Washington in November 1800, a small congressional library was housed in the Capitol. Much of the original collection was lost in the August 1814 [[Burning of Washington]] by the British during the [[War of 1812]]. Congress accepted former president [[Thomas Jefferson]]'s offer to sell his entire personal collection of 6,487 books to restore the library. The collection grew slowly and suffered another major fire in 1851, which destroyed two-thirds of Jefferson's original books.

The Library of Congress faced space shortages, understaffing, and lack of funding, until the American Civil War increased the importance of legislative research to meet the demands of a growing federal government.<ref>{{Cite web |title=The Library of Congress: A Timeline {{!}} History of the Library of Congress {{!}} About the Library {{!}} Library of Congress |url=https://www.loc.gov/about/history-of-the-library/timeline/ |access-date=2024-09-04 |website=Library of Congress, Washington, D.C. 20540 USA}}</ref>{{clarify|date=November 2024}} In 1870, the library gained the right to receive two copies of every [[Copyright law of the United States|copyrightable work]] printed in the United States; it also built its collections through acquisitions and donations. Between 1890 and 1897, a new library building, now the [[Thomas Jefferson Building]], was constructed. Two additional buildings, the [[John Adams Building]] (opened in 1939) and the [[James Madison Memorial Building]] (opened in 1980), were later added.

The LOC's Congressional Research Service provides objective non-partisan research to Congress to assist it in passing legislation. The library is open to the public for research, although only members of Congress, their staff, and library employees may borrow materials for use outside the library.<ref>{{cite web |title=FY 2019–2023 Strategic Plan of the Library of Congress |url=https://www.loc.gov/strategic-plan/ |publisher=Library of Congress |access-date=October 20, 2020}}</ref>

==History==
[[File:Loc contruction.jpg|thumb|alt=indigo progress construction photographs of the Library of Congress Jefferson Building|A series of photographs depicting the construction of the [[Thomas Jefferson Building]] between 1888 and 1894]]

===1800–1851: Origin and Jefferson's contribution===
In 1783, [[James Madison]], a [[Founding Father of the United States|Founding Father]] and the nation's fourth president, proposed creating a congressional library, but failed to gain necessary support for the idea. After the [[American Revolutionary War]], however, the Philadelphia Library Company and [[New York Society Library]] served as surrogate congressional libraries when Congress convened in those cities.<ref name=":4">Murray, Stuart. The Library: An Illustrated History (New York, Skyhouse Publishing, 2012): 155.</ref>

On April 24, 1800, the Library of Congress was established when [[John Adams]], the nation's second president, signed an [[act of Congress]], which appropriated $5,000 "for the purchase of such books as may be necessary for the use of Congress...and for fitting up a suitable apartment for containing them."<ref>{{USStat|2|55}}</ref> Books were ordered from London, forming a collection of 740 books and three maps housed in the new [[United States Capitol]].<ref name="loc history">{{cite web |title=Jefferson's Legacy: A Brief History of the Library of Congress |publisher=Library of Congress |url=https://www.loc.gov/loc/legacy/loc.html |date=March 6, 2006 |access-date=January 14, 2008 |archive-date=March 12, 2011 |archive-url=https://web.archive.org/web/20110312165046/http://www.loc.gov/loc/legacy/loc.html |url-status=live }}</ref>

Adams' successor as U.S. President, [[Thomas Jefferson]], also played a crucial role in shaping development of the Library of Congress. On January 26, 1802, Jefferson signed a bill allowing the president to appoint the [[librarian of Congress]] and establishing a [[Joint Committee on the Library]] to oversee it. The law also extended borrowing privileges to the president and vice president.<ref>{{USStat|2|128}}</ref><ref name=":2">{{Cite book |title=The library: an illustrated history |last=Murray |first=Stuart P. |publisher=Skyhorse Pub |year=2009 |isbn=9781602397064 |location=New York, NY |pages=[https://archive.org/details/libraryillustrat0000murr/page/158 158] |url=https://archive.org/details/libraryillustrat0000murr/page/158}}</ref>

In August 1814, British forces occupied Washington, D.C. and, in retaliation for American acts in Canada, [[Burning of Washington|burned]] several [[Federal government of the United States|government]] buildings, including the Library of Congress, resulting in the destructing of over 3,000 of its volumes.<ref name="loc history"/> These volumes were held in the Senate wing of the Capitol; one surviving volume was a government account book from 1810.<ref name=":2"/><ref name="HistoryBurn">{{Cite web |last=Greenpan |first=Jesse |date=August 22, 2014 |title=The British Burn Washington, D.C., 200 Years Ago |url=https://www.history.com/news/the-british-burn-washington-d-c-200-years-ago |access-date=January 8, 2021 |website=[[History.com]] |archive-date=January 8, 2021 |archive-url=https://web.archive.org/web/20210108102303/https://www.history.com/news/the-british-burn-washington-d-c-200-years-ago |url-status=live }}</ref><ref>{{Cite book |title=The Library An Illustrated History |last=Murray |first=Stuart |publisher=[[Skyhorse Publishing]] |year=2009 |location=Chicago, Illinois |pages=159}}</ref> This volume was taken by British commander [[Sir George Cockburn, 10th Baronet|George Cockburn]] as a souvenir, which was later returned to the U.S. over a century later, in 1940, by his family.<ref>{{cite book |last=Murray |first=Stuart |title=The library : an illustrated history |date=2009 |publisher=[[Skyhorse Pub.]] |location=New York, NY |isbn=978-1-60239-706-4 |url-access=registration |url=https://archive.org/details/libraryillustrat0000murr}}</ref>

Within a month, Jefferson offered to sell his large personal library<ref>{{cite web |url=http://www.librarything.com/catalog.php?view=ThomasJefferson |title=Thomas Jefferson's personal library, at LibraryThing, based on scholarship |publisher=LibraryThing |access-date=November 4, 2012 |archive-date=April 7, 2020 |archive-url=https://web.archive.org/web/20200407140544/http://www.librarything.com/catalog.php?view=ThomasJefferson |url-status=live }}</ref><ref>[http://www.librarything.com/profile/ThomasJefferson LibraryThing profile page for Thomas Jefferson's library] {{Webarchive |url=https://web.archive.org/web/20090903022310/http://www.librarything.com/profile/thomasjefferson |date=September 3, 2009 }}, summarizing contents and indicating sources</ref><ref>{{cite web |title=Jefferson's Library |url=https://www.loc.gov/exhibits/jefferson/jefflib.html |website=Library of Congress |date=April 24, 2000 |access-date=October 24, 2021 |archive-date=March 22, 2015 |archive-url=https://web.archive.org/web/20150322203344/https://www.loc.gov/exhibits/jefferson/jefflib.html |url-status=live }}</ref> as a replacement. He had reconstituted his own collection after losing part of it to a fire. Congress accepted the offer in January 1815, appropriating $23,950 to purchase his 6,487 books.<ref name="loc history"/> Some House members, including New Hampshire representative [[Daniel Webster]], opposed the purchase, wanting to exclude "books of an atheistical, irreligious, and immoral tendency".<ref name=":3">{{Cite book |title=The library : an illustrated history |last=Murray |first=Stuart P. |publisher=[[Skyhorse Pub]] |year=2009 |isbn=9781602397064 |location=Chicago |pages=[https://archive.org/details/libraryillustrat0000murr/page/162 162] |url=https://archive.org/details/libraryillustrat0000murr/page/162}}</ref>

Jefferson's collection, gathered over 50 years, covered various subjects and languages, including topics not typically found in a legislative library.<ref name=":4"/> He believed all subjects had a place in the Library of Congress, stating:

<blockquote>I do not know that it contains any branch of science which Congress would wish to exclude from their collection; there is, in fact, no subject to which a Member of Congress may not have occasion to refer.<ref name=":3"/></blockquote>

Jefferson's library was a working collection for a scholar, not for display. It doubled the size of the original library, transforming it from a specialist's library to a more general one.<ref>Murray, Stuart A.P. ''The Library: An Illustrated History''. Skyhorse Publishing, 2012. 9781616084530, pp. 161</ref> He organized his books based on [[Francis Bacon]]'s [[Works by Francis Bacon#Scientific works|organization of knowledge]], grouping them into Memory, Reason, and Imagination with 44 subdivisions.<ref>{{Cite book |last=Murray |first=Stuart |url=https://archive.org/details/libraryillustrat0000murr/page/162/mode/2up |title=The Library: An Illustrated History |publisher=Skyhorse Publishing |year=2009 |isbn=978-1-60239-706-4 |location=New York |pages=162 |url-access=registration}}</ref> The library used this scheme until the late 19th century when librarian [[Herbert Putnam]] introduced the [[Library of Congress Classification]], now applying to over 138 million items.

A February 24, 1824, report from the [[Committee of Ways and Means]] recommended a $5,000 appropriation for the Library of Congress, noting the need to improve its collections in "Law, Politics, Commerce, History, and Geography," which were crucial for Congress.<ref name="gi">{{cite web |title=H. Rept. 18–69 – Report of the Committee of Ways and Means, to whom was referred a resolution of the House of Representatives of 21st January, 1824, instructing said committee to inquire into the expediency of appropriating $5,000 for the use of the Library of Congress, accompanying a bill for effecting that object. February 24, 1824. Read, and, with the bill, committed to a Committee of the Whole House |url=https://www.govinfo.gov/app/details/SERIALSET-00105_00_00-070-0069-0000 |website=GovInfo |publisher=[[United States Government Publishing Office|U.S. Government Printing Office]] |access-date=June 19, 2023 |url-status=live |archive-url=https://web.archive.org/web/20230619211134/https://www.govinfo.gov/app/details/SERIALSET-00105_00_00-070-0069-0000 |archive-date=June 19, 2023 }}</ref>

===1851–1865: Weakening===
[[File:The_Library_of_Congress_in_the_U.S._Capitol_Building_LCCN2010649528.jpg|thumb|The Library of Congress, then located in the [[United States Capitol|Capitol Building]] in 1853]]
On December 24, 1851, the largest fire in the library's history destroyed 35,000 books, two-thirds of the library's collection, and two-thirds of [[Thomas Jefferson]]'s original transfer. Congress appropriated $168,700 to replace the lost books in 1852 but not to acquire new materials.<ref name="Library of Congress">{{cite book |last=Cole |first=J.Y. |title=Jefferson's Legacy: a brief history of the Library of Congress |date=1993 |publisher=Library of Congress |location=Washington, D.C. |page=14}}</ref> (By 2008, the librarians of Congress had found replacements for all but 300 of the works that had been documented as being in Jefferson's original collection.<ref>{{cite journal |title=Thomas Jefferson's Library |url=https://www.loc.gov/loc/lcib/0806/jefferson.html |last=Fineberg |first=Gail |journal=The Gazette |publisher=Library of Congress |date=June 2007 |volume=67 |number=6 |access-date=January 4, 2015 |archive-date=July 6, 2014 |archive-url=https://web.archive.org/web/20140706040043/http://www.loc.gov/loc/lcib/0806/jefferson.html |url-status=live }}</ref>) This marked the start of a conservative period in the library's administration by librarian [[John Silva Meehan]] and joint committee chairman [[James Pearce (American politician)|James A. Pearce]], who restricted the library's activities.<ref name="Library of Congress"/> Meehan and Pearce's views about a restricted scope for the Library of Congress reflected those shared by members of Congress.

While Meehan was a librarian, he supported and perpetuated the notion that "the congressional library should play a limited role on the national scene and that its collections, by and large, should emphasize American materials of obvious use to the U.S. Congress."<ref>{{cite journal |last=Cole |first=J.Y. |s2cid=142764409 |title=The Library of Congress Becomes a World Leader, 1815–2005 |journal=Libraries & Culture |date=2005 |volume=40 |issue=3 |page=386 |doi=10.1353/lac.2005.0046}}</ref> In 1859, Congress transferred the library's public document distribution activities to the [[United States Department of the Interior|Department of the Interior]] and its international book exchange program to the [[United States Department of State|Department of State]].<ref>{{cite web |last=Interior Library |title=History of the Interior Library |url=https://www.doi.gov/library/about/history |website=U.S. Department for the Interior |date=August 4, 2015 |access-date=April 30, 2018 |archive-date=May 21, 2017 |archive-url=https://web.archive.org/web/20170521205728/https://www.doi.gov/library/about/history |url-status=live }}</ref>

During the 1850s, [[Smithsonian Institution]] librarian [[Charles Coffin Jewett]] aggressively tried to develop the Smithsonian as the United States national library. His efforts were rejected by Smithsonian secretary [[Joseph Henry]], who advocated a focus on scientific research and publication.<ref>{{cite book |last=Smithsonian Institution |title=An Account Of The Smithsonian: Its Origin, History, Objects and Achievements |date=1904 |location=Washington, D.C. |page=12}}</ref> To reinforce his intentions for the Smithsonian, Henry established laboratories, developed a robust physical sciences library, and started the ''[[Smithsonian Contributions to Knowledge]]'', the first of many publications intended to disseminate research results.<ref>{{cite book |last=Mearns |first=D.C. |title=The Story Up to Now: The Library of Congress, 1800–1946 |date=1946 |publisher=Government Printing Office |location=Washington, D.C. |pages=100}}</ref> For Henry, the Library of Congress was the obvious choice as the national library. Unable to resolve the conflict, Henry dismissed Jewett in July 1854.

In 1865, the Smithsonian building, also called the Castle due to its Norman architectural style, was severely damaged by fire. This incident presented Henry with an opportunity related to the Smithsonian's non-scientific library. Around this time, the Library of Congress was planning to build and relocate to the new [[Thomas Jefferson Building]], designed to be fireproof.<ref>{{cite web |last=Library of Congress |title=Annual Report of the Librarian of Congress 1866 |url=https://www.copyright.gov/reports/annual/archive/ar-1866.pdf |website=U.S. Copyright Office |access-date=April 30, 2018 |archive-date=April 27, 2017 |archive-url=https://web.archive.org/web/20170427060600/https://www.copyright.gov/reports/annual/archive/ar-1866.pdf |url-status=live }}</ref> Authorized by an act of Congress, Henry transferred the Smithsonian's non-scientific library of 40,000 volumes to the Library of Congress in 1866.<ref>{{cite web |last=Gwinn |first=Nancy |title=History |url=https://library.si.edu/about/history |website=Smithsonian Libraries |access-date=April 30, 2018 |archive-date=May 1, 2018 |archive-url=https://web.archive.org/web/20180501004949/https://library.si.edu/about/history |url-status=live }}</ref>

In 1861, President [[Abraham Lincoln]] appointed [[John G. Stephenson]] as [[Librarian of Congress]]; the appointment is regarded as the most political to date.<ref name="John G Stephenson">{{cite web |last=Library of Congress |title=John G Stephenson |url=https://www.loc.gov/about/about-the-librarian/previous-librarians-of-congress/john-g-stephenson/ |website=John G Stephenson – Previous Librarians of Congress |access-date=April 30, 2018 |archive-date=April 21, 2018 |archive-url=https://web.archive.org/web/20180421031400/https://www.loc.gov/about/about-the-librarian/previous-librarians-of-congress/john-g-stephenson/ |url-status=live }}</ref> Stephenson was a physician and spent equal time serving as librarian and as a physician in the [[Union Army]]. He could manage this division of interest because he hired [[Ainsworth Rand Spofford]] as his assistant.<ref name="John G Stephenson"/> Despite his new job, Stephenson focused on the war. Three weeks into his term as Librarian of Congress, he left Washington, D.C., to serve as a volunteer [[aide-de-camp]] at the battles of [[Battle of Chancellorsville|Chancellorsville]] and [[Battle of Gettysburg|Gettysburg]] during the [[American Civil War]].<ref name="John G Stephenson"/> Stephenson's hiring of Spofford, who directed the library in his absence, may have been his most significant achievement.<ref name="John G Stephenson"/>

===1865–1897: Spofford's expansion===
[[File:Library of Congress, showing three levels crowded with stacks of books and newspapers LCCN2017646700.jpg|alt=Library of Congress stacks in the Capitol building|thumb|Library of Congress in the Capitol Building in the 1890s]]
Librarian [[Ainsworth Rand Spofford]], who directed the Library of Congress from 1865 to 1897, built broad bipartisan support to develop it as a national library and a legislative resource.<ref>{{Cite journal |last=Aikin |first=Jane |date=2010 |title=Histories of the Library of Congress |journal=Libraries & the Cultural Record |volume=45 |issue=1 |pages=11–12 |doi=10.1353/lac.0.0113 |issn=1932-4855 |jstor=20720636}}</ref><ref>{{Cite news |last=Weeks |first=Linton |date=December 13, 1999 |title=A Bicentennial for the Books |url=https://www.washingtonpost.com/wp-srv/WPcap/1999-12/13/028r-121399-idx.html |access-date=October 3, 2021 |newspaper=[[The Washington Post]] |archive-date=January 18, 2023 |archive-url=https://web.archive.org/web/20230118182234/https://www.washingtonpost.com/wp-srv/WPcap/1999-12/13/028r-121399-idx.html |url-status=live }}</ref> He was aided by expansion of the federal government after the war and a favorable political climate. He began comprehensively collecting [[Americana (culture)|Americana]] and [[American literature]], led the construction of a new building to house the library, and transformed the librarian of Congress position into one of strength and independence. Between 1865 and 1870, Congress appropriated funds for the construction of the [[Thomas Jefferson Building]], placed all [[copyright registration]] and [[Copyright deposit|deposit]] activities under the library's control, and restored the international book exchange. The library also acquired the vast libraries of the Smithsonian and of historian [[Peter Force]], strengthening its scientific and Americana collections significantly. By 1876, the Library of Congress had 300,000 volumes; it was tied with the [[Boston Public Library]] as the nation's largest library. It moved from the Capitol building to its new headquarters in 1897 with more than 840,000 volumes, 40 percent of which had been acquired through copyright deposit.<ref name="loc history"/>

A year before the library's relocation, the Joint Library Committee held hearings to assess the condition of the library and plan for its future growth and possible reorganization. Spofford and six experts sent by the [[American Library Association]]<ref>These included future Librarian of Congress [[Herbert Putnam]] and [[Melvil Dewey]] of the [[New York State Library]].</ref> testified that the library should continue its expansion to become a true national library. Based on the hearings, Congress authorized a budget that allowed the library to more than double its staff, from 42 to 108 persons. Senators [[Justin Morrill]] of Vermont and [[Daniel W. Voorhees]] of Indiana were particularly helpful in gaining this support. The library also established new administrative units for all aspects of the collection. In its bill, Congress strengthened the role of librarian of Congress: it became responsible for governing the library and making staff appointments. As with presidential Cabinet appointments, the Senate was required to approve presidential appointees to the position.<ref name="loc history"/>

In 1893, [[Bessie Dwyer|Elizabeth Dwyer]] became the first woman to be appointed to the staff of the library.<ref>U.S. Civil Service Commission, Women in the Federal Service (Washington, D.C.: Civil Service Commission, 1938), 3–6, 9.</ref>

===1897–1939: Post-reorganization===
[[File:Library of Congress, Washington, D.C. - c. 1902.jpg|thumb|alt=Congressional Library. View from the U.S. Capitol|A 1902 aerial view from the [[United States Capitol]] of the five-year old Library of Congress in its new building that was renamed the [[Thomas Jefferson Building]] in 1980 in honor of [[Thomas Jefferson]]]]
[[File:Library of Congress and lawn.jpg|alt=photograph of west colonnade by Carol M. Highsmith|thumb|[[Thomas Jefferson Building]], built 1890–1897, the Library of Congress's main building, on [[Capitol Hill]], Washington, D.C., showing West side colonnade of Jefferson Building, viewed from across First Street and the grounds of the East Front of the [[United States Capitol|U.S. Capitol]]]]
With this support and the 1897 reorganization upon moving into its new home, the Library of Congress began to grow and develop more rapidly. Librarian Spofford's successor [[John Russell Young]] overhauled the library's bureaucracy, used his connections as a former diplomat to acquire more materials from around the world, and established the library's first assistance programs for the blind and physically disabled, with the establishment of the [[National Library Service for the Blind and Print Disabled]].

Librarian Young's successor [[Herbert Putnam]] held the office for forty years of the 20th century from 1899 to 1939. Two years after he took office, the library became the first in the United States to hold one million volumes.<ref name="loc history"/> Putnam focused his efforts to make the library more accessible and useful for the public and for other libraries. He instituted the [[interlibrary loan]] service, transforming the Library of Congress into what he referred to as a "library of last resort".<ref name="interlibrary loan">{{cite web |title=Interlibrary Loan (Collections Access, Management and Loan Division, Library of Congress) |url=https://www.loc.gov/rr/loan/ |date=October 25, 2007 |publisher=Library of Congress website |access-date=December 4, 2007 |archive-date=November 29, 2007 |archive-url=https://web.archive.org/web/20071129021335/http://www.loc.gov/rr/loan/ |url-status=live }}</ref> Putnam also expanded library access to "scientific investigators and duly qualified individuals", and began publishing [[primary sources]] for the benefit of scholars.<ref name="loc history"/>

During Putnam's tenure, the library broadened the diversity of its acquisitions. In 1903, Putnam persuaded President [[Theodore Roosevelt]] to use an executive order to transfer the papers of the [[Founding Fathers of the United States|Founding Fathers]] from the State Department to the Library of Congress.

Putnam also expanded foreign acquisitions, including the 1904 purchase of a 4,000-volume library of Indica, the 1906 purchase of G. V. Yudin's 80,000-volume Russian library, the 1908 Schatz collection of early opera [[libretto]]s, and the early 1930s purchase of the Russian Imperial Collection, consisting of 2,600 volumes from the library of the [[Romanov family]] on a variety of topics. Collections of [[Hebraica]], Chinese, and Japanese works were also acquired. On one occasion, Congress initiated an acquisition: in 1929 Congressman [[Ross Collins]] (D-Mississippi) gained approval for the library to purchase [[Otto Vollbehr]]'s collection of [[incunabula]] for $1.5&nbsp;million. This collection included one of three remaining perfect [[vellum]] copies of the [[Gutenberg Bible]].<ref name="loc history"/><ref>{{cite journal |last=Snapp |first=Elizabeth |title=The Acquisition of the Vollbehr Collection of Incunabula for the Library of Congress |journal=The Journal of Library History |volume=10 |issue=2 |date=April 1975 |pages=152–161 |publisher=University of Texas Press |jstor=25540624}} (restricted access)</ref>
[[File:Gutenberg Bible.jpg|thumb|alt=Gutenberg Bible on display at the Library of Congress|[[Gutenberg Bible]] on display at the Library of Congress]]
Putnam established the [[Legislative Reference Service]] (LRS) in 1914 as a separative administrative unit of the library. Based on the [[Progressive Era]]'s philosophy of science to be used to solve problems, and modeled after successful research branches of state legislatures, the LRS would provide informed answers to Congressional research inquiries on almost any topic. Congress passed in 1925 an act allowing the Library of Congress to establish a trust fund board to accept donations and endowments, giving the library a role as a [[patron of the arts]]. The library received donations and endowments by such prominent wealthy individuals as [[John D. Rockefeller]], James B. Wilbur, and [[Archer M. Huntington]]. Gertrude Clarke Whittall donated five [[List of Stradivarius instruments#Violins|Stradivarius violins]] to the library. [[Elizabeth Sprague Coolidge]]'s donations paid for a [[concert hall]] to be constructed within the Library of Congress building and an [[honorarium]] established for the Music Division to pay live performers for concerts. A number of chairs and consultantships were established from the donations, the most well-known of which is the [[Poet Laureate Consultant in Poetry to the Library of Congress|Poet Laureate Consultant]].<ref name="loc history"/>

The library's expansion eventually filled the library's Main Building, although it used shelving expansions in 1910 and 1927. The library needed to expand into a new structure. Congress acquired nearby land in 1928 and approved construction of the Annex Building (later known as the [[John Adams Building]]) in 1930. Although delayed during the [[Great Depression|Depression]] years, it was completed in 1938 and opened to the public in 1939.<ref name="loc history"/>

===1939–1987: National versus legislative role===
[[File:Adams Building 1938 (31274181753).jpg|thumb|What is now the Library of Congress's second structure of the [[John Adams Building]] that opened in 1939 on [[Capitol Hill]] in Washington, D.C.]]
In 1939, following Putnam's retirement, President [[Franklin D. Roosevelt]] appointed poet and writer [[Archibald MacLeish]] as his successor. Occupying the post from 1939 to 1944 during the height of [[World War II]], MacLeish became the most widely known librarian of Congress in the library's history. MacLeish encouraged librarians to oppose [[totalitarianism]] on behalf of democracy; dedicated the South Reading Room of the Adams Building to Thomas Jefferson, and commissioned artist [[Ezra Winter]] to paint four themed murals for the room. He established a "democracy alcove" in the Main Reading Room of the Jefferson Building for essential documents such as the Declaration of Independence, the Constitution, and ''[[The Federalist Papers]]''. The Library of Congress assisted during the war effort, ranging from storage of the [[United States Declaration of Independence|Declaration of Independence]] and the [[United States Constitution]] in [[Fort Knox]] for safekeeping to researching weather data on the [[Himalayas]] for [[United States Air Force|Air Force]] pilots. MacLeish resigned in 1944 when appointed as Assistant Secretary of State.

President [[Harry Truman]] appointed [[Luther H. Evans]] as Librarian of Congress. Evans, who served until 1953, expanded the library's acquisitions, cataloging, and bibliographic services. But he is best known for creating Library of Congress Missions worldwide. Missions played a variety of roles in the postwar world: the mission in San Francisco assisted participants in the [[meeting that established the United Nations]], the mission in Europe acquired European publications for the Library of Congress and other American libraries, and the mission in Japan aided in the creation of the [[National Diet Library]].<ref name="loc history"/>

[[File:South Reading Room, with murals by Ezra Winter. Library of Congress John Adams Building, Washington, D.C. LCCN2007687090.jpg|thumb|The Adams Building – South Reading Room, with murals by [[Ezra Winter]]]]

Evans' successor [[Lawrence Quincy Mumford]] took over in 1953. During his tenure, lasting until 1974, Mumford directed the initiation of construction of the [[James Madison Memorial Building]], the third Library of Congress building on Capitol Hill. Mumford led the library during the government's increased educational spending. The library was able to establish new acquisition centers abroad, including in [[Cairo]] and New Delhi. In 1967, the library began experimenting with [[book preservation]] techniques through a Preservation Office. This has developed as the most extensive library research and conservation effort in the United States.

During Mumford's administration, the last significant public debate occurred about the Library of Congress's role as both a legislative and national library. Asked by Joint Library Committee chairman Senator [[Claiborne Pell]] (D-RI) to assess operations and make recommendations, Douglas Bryant of [[Harvard University Library]] proposed several institutional reforms. These included expanding national activities and services and various organizational changes, all of which would emphasize the library's federal role rather than its legislative role. Bryant suggested changing the name of the Library of Congress, a recommendation rebuked by Mumford as "unspeakable violence to tradition." The debate continued within the library community for some time. The [[Legislative Reorganization Act of 1970]] renewed emphasis for the library on its legislative roles, requiring a greater focus on research for Congress and congressional committees, and renaming the Legislative Reference Service as the [[Congressional Research Service]].<ref name="loc history"/>
[[File:JamesMadisonMemorialBuilding.jpg|thumb|[[James Madison Memorial Building]] opened in 1980 <ref>{{Cite web |last=Cole |first=John Y. |title=The James Madison Building (On These Walls: Inscriptions and Quotations in the Buildings of the Library of Congress, by John Y. Cole) |url=https://www.loc.gov/loc/walls/madison.html |access-date=February 20, 2022 |website=loc.gov |archive-date=February 7, 2011 |archive-url=https://web.archive.org/web/20110207045540/http://www.loc.gov/loc/walls/madison.html |url-status=live }}</ref>]]
After Mumford retired in 1974, President [[Gerald Ford]] appointed historian [[Daniel J. Boorstin]] as a librarian. Boorstin's first challenge was to manage the relocation of some sections to the new Madison Building, which took place between 1980 and 1982. With this accomplished, Boorstin focused on other areas of library administration, such as acquisitions and collections. Taking advantage of steady budgetary growth, from $116&nbsp;million in 1975 to over $250&nbsp;million by 1987, Boorstin enhanced institutional and staff ties with scholars, authors, publishers, cultural leaders, and the business community. His activities changed the post of librarian of Congress so that by the time he retired in 1987, ''[[The New York Times]]'' called this office "perhaps the leading intellectual public position in the nation."

===1987–2015 Billington leadership, digitization and programs ===

In 1987, President [[Ronald Reagan]] nominated historian [[James H. Billington]] as the thirteenth librarian of Congress, and the [[United States Senate|U.S. Senate]] unanimously confirmed the appointment.<ref name="loc.gov">{{Cite web |title=Key Milestones of James H. Billington's Tenure {{!}} News Releases – Library of Congress |url=https://www.loc.gov/today/pr/2015/15-105.html |website=Loc.gov |access-date=September 22, 2015 |archive-date=September 6, 2015 |archive-url=https://web.archive.org/web/20150906013633/http://www.loc.gov/today/pr/2015/15-105.html |url-status=live }}</ref>

Under Billington's leadership, the library doubled the size of its analog collections from 85.5&nbsp;million items in 1987 to more than 160 million items in 2014. At the same time, it established new programs and employed new technologies to "get the champagne out of the bottle". These included:
*[[American Memory]] created in 1990, which became the [[National Digital Library Program|National Digital Library]] in 1994. It provides free access online to digitized American history and culture resources, including [[primary source]]s, with curatorial explanations to support use in [[K-12 education]].<ref>{{Cite web |title=American Memory from the Library of Congress – Home Page |url=http://memory.loc.gov/ammem/index.html |website=Memory.loc.gov |access-date=September 22, 2015 |archive-date=May 4, 1999 |archive-url=https://web.archive.org/web/19990504160400/http://memory.loc.gov/ammem/index.html |url-status=live }}</ref>
*[[THOMAS.gov]] website launched in 1994 to provide free public access to U.S. federal legislative information with ongoing updates; and [[Congress.gov]] website to provide a state-of-the-art framework for both Congress and the public in 2012;<ref>{{Cite web |title=Congress.gov {{!}} Library of Congress |url=https://www.congress.gov/ |website=congress.gov |access-date=September 22, 2015 |archive-date=March 25, 2018 |archive-url=https://web.archive.org/web/20180325080754/https://www.congress.gov/ |url-status=live }}</ref>
*[[National Book Festival]], founded in 2001 with First Lady [[Laura Bush]],<ref>Oder, Norman. "First Lady Launches Book Festival." ''Library Journal'' 126, no. 14 (2001): 17</ref> has attracted more than 1,000 authors and a million guests to the [[National Mall]] and the [[Washington Convention Center]] to celebrate reading. With a major gift from [[David Rubenstein]] in 2013, the library established the [[Library of Congress Literacy Awards]] to recognize and support achievements in improving literacy in the U.S. and abroad;<ref>{{Cite web |title=2015 Book Festival {{!}} National Book Festival – Library of Congress |url=https://www.loc.gov/bookfest/ |website=Loc.gov |access-date=September 22, 2015 |archive-date=February 3, 2023 |archive-url=https://web.archive.org/web/20230203043133/https://www.loc.gov/programs/national-book-festival/about-this-program/ |url-status=live }}</ref>
*[[John W. Kluge Center|Kluge Center]], started with a grant of $60&nbsp;million from [[John W. Kluge]] in 2000, brings international scholars and researchers to use library resources and to interact with policymakers and the public. It hosts public lectures and scholarly events, provides endowed Kluge fellowships, and awards the [[Kluge Prize|Kluge Prize for the Study of Humanity]] (now worth $1.5&nbsp;million), the first Nobel-level international prize for lifetime achievement in the humanities and social sciences (subjects not included in the [[Nobel awards]]);<ref>{{Cite web |title=The John W. Kluge Center – Library of Congress |url=https://www.loc.gov/loc/kluge/ |website=Loc.gov |access-date=September 22, 2015 |archive-date=September 20, 2015 |archive-url=https://web.archive.org/web/20150920064635/http://www.loc.gov/loc/kluge/ |url-status=live }}</ref>
*[[Open World Leadership Center]], established in 2000; by 2015 this program administered 23,000 professional exchanges for emerging post-Soviet leaders in Russia, Ukraine, and other successor states of the former [[USSR]]. Open World began as a Library of Congress project, and later was established as an independent agency in the legislative branch.<ref>{{Cite web |title=Founding Chairman {{!}} OpenWorld |url=http://www.openworld.gov/about-us/founding-chairman |website=openworld.gov |access-date=September 22, 2015 |archive-url=https://web.archive.org/web/20150905053401/http://www.openworld.gov/about-us/founding-chairman |archive-date=September 5, 2015 |url-status=dead }}</ref>
*[[Veterans History Project]], congressionally mandated in 2000 to collect, preserve, and make accessible the personal accounts of American war veterans from [[World War I]] to the present day;<ref>{{Cite web |title=Veterans History Project (Library of Congress) |url=https://www.loc.gov/vets/ |website=Loc.gov |access-date=September 22, 2015 |archive-date=September 23, 2015 |archive-url=https://web.archive.org/web/20150923204512/http://www.loc.gov/vets/ |url-status=live }}</ref>
*[[National Audio-Visual Conservation Center]] opened in 2007 at a 45-acre site in [[Culpeper, Virginia]], established with a gift of more than $150&nbsp;million by the [[Packard Humanities Institute]], and $82.1&nbsp;million in additional support from Congress.

[[File:Erotica at Library of Congress, Washington D.C. 02223u original.jpg|thumb|upright|alt=mural painting entitled ''Erotica'', by George Randolph Bars|''Erotica'', mural painting by [[George Randolph Barse]] in the library's main building]]
Since 1988, the library has administered the [[National Film Preservation Board]]. Established by congressional mandate, it selects twenty-five American films annually for preservation and inclusion in the [[National Film Registry]], a collection of American films, for which the Library of Congress accepts nominations each year.<ref>{{Cite web |title=Film Registry {{!}} National Film Preservation Board {{!}} Programs {{!}} Library of Congress |url=https://www.loc.gov/programs/national-film-preservation-board/film-registry/ |access-date=March 25, 2022 |website=Library of Congress |archive-date=February 25, 2021 |archive-url=https://web.archive.org/web/20210225023526/https://loc.gov/programs/national-film-preservation-board/film-registry |url-status=live }}</ref> There also exists a [[National Recording Registry]] administered by the [[National Recording Preservation Board]] that serves a similar purpose for music and sound recordings.

The library has made some of these available on the Internet for free streaming and additionally has provided brief essays on the films that have been added to the registry.<ref>Dargis, Manohla (April 3, 2020), [https://www.nytimes.com/2020/04/03/movies/library-congress-streaming-free.html "Film Treasures, Streaming Courtesy of the Library of Congress"] {{Webarchive |url=https://web.archive.org/web/20200414222620/https://www.nytimes.com/2020/04/03/movies/library-congress-streaming-free.html |date=April 14, 2020 }}, ''The New York Times'', with links to videos and collections, and on April 4, 2020, Section C, Page 1, New York edition with the headline: ''An Online Trove of Film Treasures''</ref><ref>{{Cite web |title=Complete National Film Registry Listing |url=https://www.loc.gov/programs/national-film-preservation-board/film-registry/complete-national-film-registry-listing/ |access-date=March 25, 2022 |website=Library of Congress |archive-date=March 3, 2020 |archive-url=https://web.archive.org/web/20200303055247/https://www.loc.gov/programs/national-film-preservation-board/film-registry/complete-national-film-registry-listing/ |url-status=live }}</ref> By 2015, the librarian had named 650 films to the registry.<ref>{{Cite magazine |title=Inside the Nuclear Bunker Where America Preserves Its Movie History |magazine=Wired |url=https://www.wired.com/2015/07/film-preservation/ |access-date=September 22, 2015 |archive-date=September 12, 2015 |archive-url=https://web.archive.org/web/20150912060944/http://www.wired.com/2015/07/film-preservation |url-status=live }}</ref> The films in the collection date from the earliest period to ones produced more than ten years ago; they are selected from nominations submitted to the board. Further programs included:

*[[Gershwin Prize for Popular Song]],<ref>{{Cite web |title=Gershwin Prize |website=Library of Congress |url=https://www.loc.gov/about/awards-and-honors/gershwin-prize/ |access-date=September 22, 2015 |archive-date=September 20, 2015 |archive-url=https://web.archive.org/web/20150920075833/http://www.loc.gov/about/awards-and-honors/gershwin-prize/ |url-status=live }}</ref> was launched in 2007 to honor the work of an artist whose career reflects lifetime achievement in song composition. Winners have included [[Paul Simon]], [[Stevie Wonder]], [[Paul McCartney]], [[Burt Bacharach]] and [[Hal David]], [[Carole King]], [[Billy Joel]], and [[Willie Nelson]], as of 2015. The library also launched the [[Library of Congress Living Legend|Living Legend Awards]] in 2000 to honor artists, activists, filmmakers, and others who have contributed to America's diverse cultural, scientific, and social heritage;
*Fiction Prize (now the [[Library of Congress Prize for American Fiction]]) was started in 2008 to recognize distinguished lifetime achievement in the writing of fiction.<ref>{{Cite web |title=Fiction Prize |website=Library of Congress |url=https://www.loc.gov/about/awards-and-honors/fiction-prize/ |access-date=September 22, 2015 |archive-date=September 20, 2015 |archive-url=https://web.archive.org/web/20150920075033/http://www.loc.gov/about/awards-and-honors/fiction-prize/ |url-status=live }}</ref>
*[[World Digital Library]], established in association with [[UNESCO]] and 181 partners in 81 countries in 2009, makes copies of professionally curated primary materials of the world's varied cultures freely available online in multiple languages.<ref name="Background - World Digital Library">{{Cite web |title=Background – World Digital Library |url=http://www.wdl.org/en/background/ |website=wdl.org |access-date=September 22, 2015 |archive-date=September 23, 2015 |archive-url=https://web.archive.org/web/20150923090200/http://www.wdl.org/en/background/ |url-status=live }}</ref>
*National Jukebox, launched in 2011, provides streaming free online access to more than 10,000 out-of-print music and spoken-word recordings.<ref>{{Cite web |title=National Jukebox LOC.gov |url=https://www.loc.gov/jukebox/ |website=Loc.gov |access-date=September 22, 2015 |archive-date=September 29, 2015 |archive-url=https://web.archive.org/web/20150929024224/http://www.loc.gov/jukebox/ |url-status=live }}</ref>
*BARD was started in 2013; it is a digital, talking books [[mobile app]] for [[braille]] and audio reading downloads, in partnership with the library's [[National Library Service for the Blind and Print Disabled]]. It enables free downloads of audio and braille books to mobile devices via the [[App Store (iOS)|Apple App Store]].<ref>{{Cite web |title=NLS Home |url=https://www.loc.gov/nls/ |website=Loc.gov |access-date=September 22, 2015 |archive-date=September 23, 2015 |archive-url=https://web.archive.org/web/20150923213419/http://www.loc.gov/nls/ |url-status=live }}</ref>

During Billington's tenure, the library acquired [[Gilbert du Motier, marquis de Lafayette|General Lafayette]]'s papers in 1996 from a castle at La Grange, France; they had previously been inaccessible.

It also acquired the only copy of the 1507 [[Waldseemüller map|Waldseemüller world map]] ("America's birth certificate") in 2003; it is on permanent display in the library's Thomas Jefferson Building.

Using privately raised funds, the Library of Congress has created a reconstruction of Thomas Jefferson's original library. This has been on permanent display in the Jefferson building since 2008.<ref>{{Cite web |title=Thomas Jefferson's Library {{!}} Exhibitions – Library of Congress |url=http://loc.gov/exhibits/thomas-jeffersons-library/ |website=loc.gov |date=April 11, 2008 |access-date=September 22, 2015 |archive-date=October 2, 2015 |archive-url=https://web.archive.org/web/20151002062914/http://www.loc.gov/exhibits/thomas-jeffersons-library/ |url-status=live }}</ref>
[[File:Minerva of Peace.jpg|thumb|upright|alt=mosaic wall decoration ''Minerva of Peace mosaic'' by Elihu Vedder|''[[Minerva]] of Peace'', [[mosaic]] by [[Elihu Vedder]] in the library's main building|right]]

Under Billington, public spaces of the Jefferson Building were enlarged and technologically enhanced to serve as a national exhibition venue. It has hosted more than 100 exhibitions.<ref>{{Cite web |title=All Exhibitions |website=Library of Congress|url=https://www.loc.gov/exhibits/all/ |access-date=|archive-date=September 16, 2015|url-status=live |archive-url=https://web.archive.org/web/20150916101555/http://www.loc.gov/exhibits/all/ }}</ref> These included exhibits on the [[Vatican Library]] and the {{Lang|fr|[[Bibliothèque Nationale de France]] |italic= no}}, several on the Civil War and Lincoln, on African-American culture, on Religion and the founding of the American Republic, the Early Americas (the Kislak Collection became a permanent display), on the global celebration commemorating the 800th anniversary of [[Magna Carta]], and on early American printing, featuring the Rubenstein [[Bay Psalm Book]].

Onsite access to the Library of Congress has been increased. Billington gained an underground connection between the new U.S. Capitol Visitors Center and the library in 2008 to increase both congressional usage and public tours of the library's Thomas Jefferson Building.<ref name="loc.gov"/>

In 2001, the library began a [[mass deacidification]] program, to extend the lifespan of almost 4 million volumes and 12&nbsp;million manuscript sheets. In 2002, a new storage facility was completed at [[Fort Meade, Maryland]],<ref name="GeneralInfo"/> where a collection of storage modules have preserved and made accessible more than 4 million items from the library's analog collections.{{citation needed|date=February 2023}}

Billington established the Library Collections Security Oversight Committee in 1992 to improve protection of the collections, and also the Library of Congress Congressional Caucus in 2008 to draw attention to the library's curators and collections. He created the library's first Young Readers Center in the Jefferson Building in 2009, and the first large-scale summer intern (Junior Fellows) program for university students in 1991.<ref>{{Cite web |title=2015 Junior Fellows Summer Intern Program Home (Library of Congress) |url=https://www.loc.gov/hr/jrfellows/ |website=Loc.gov |access-date=September 22, 2015 |archive-date=September 30, 2015 |archive-url=https://web.archive.org/web/20150930073544/http://www.loc.gov/hr/jrfellows/ |url-status=live }}</ref>

Under Billington, the library sponsored the Gateway to Knowledge in 2010 to 2011, a mobile exhibition to ninety sites, covering all states east of the Mississippi, in a specially designed eighteen-wheel truck. This increased public access to library collections off-site, particularly for rural populations, and helped raise awareness of what was also available online.<ref>{{Cite web |title=Gateway to Knowledge – Educational Resources – Library of Congress |url=https://www.loc.gov/gateway/resources.html |website=Loc.gov |access-date=September 22, 2015 |archive-date=September 30, 2015 |archive-url=https://web.archive.org/web/20150930012253/http://www.loc.gov/gateway/resources.html |url-status=live }}</ref>

Billington raised more than half a billion dollars of private support to supplement Congressional appropriations for library collections, programs, and digital outreach. These private funds helped the library to continue its growth and outreach in the face of a 30% decrease in staffing, caused mainly by legislative appropriations cutbacks. He created the library's first development office for private fundraising in 1987. In 1990, he established the James Madison Council, the library's first national private sector donor-support group. In 1987, Billington also asked the [[Government Accountability Office]] (GAO) to conduct the first library-wide audit. He created the first [[Office of the Inspector General]] at the library to provide regular, independent reviews of library operations. This precedent has resulted in regular annual financial audits at the library; it has received unmodified ("clean") opinions from 1995 onward.<ref name="loc.gov"/> In April 2010, the library announced plans to archive all public communication on Twitter, including all communication since Twitter's launch in March 2006.<ref name=Grier>{{cite news |first=Peter |last=Grier |url=http://www.csmonitor.com/USA/Politics/The-Vote/2010/0416/Twitter-hits-Library-of-Congress-Would-Founding-Fathers-tweet |title=Twitter hits Library of Congress: Would Founding Fathers tweet? |work=[[Christian Science Monitor]] |date=April 16, 2010 |access-date=January 4, 2015 |archive-date=October 30, 2014 |archive-url=https://web.archive.org/web/20141030021433/http://www.csmonitor.com/USA/Politics/The-Vote/2010/0416/Twitter-hits-Library-of-Congress-Would-Founding-Fathers-tweet |url-status=live }}</ref> {{As of|2015}}, the Twitter archive remains unfinished.<ref>{{cite journal |last=Zimmer |first=Michael |title=The Twitter Archive at the Library of Congress: Challenges for information practice and information policy |url=http://firstmonday.org/ojs/index.php/fm/article/view/5619/4653 |journal=First Monday |year=2015 |doi=10.5210/fm.v20i7.5619 |access-date=November 3, 2015 |archive-date=September 10, 2015 |archive-url=https://web.archive.org/web/20150910143844/http://firstmonday.org/ojs/index.php/fm/article/view/5619/4653 |url-status=live |doi-access=free |url-access=subscription }}</ref>

Before retiring in 2015, after 28 years of service, Billington had come "under pressure" as librarian of Congress.<ref>"[http://www.mcclatchydc.com/news/nation-world/national/article41942157.html Librarian of Congress gets a Due Date] {{Webarchive |url=https://web.archive.org/web/20210202124750/https://www.mcclatchydc.com/news/nation-world/national/article41942157.html |date=February 2, 2021 }}" by Maria Recio, McClatchy DC, Oct. 30. 2015</ref> This followed a GAO report that described a "work environment lacking central oversight" and faulted Billington for "ignoring repeated calls to hire a chief information officer, as required by law."<ref>[https://www.washingtonpost.com/entertainment/museums/americas-national-library-is-behind-the-digital-curve-a-new-report-finds/2015/03/31/fad54c3a-d3fd-11e4-a62f-ee745911a4ff_story.html America's 'national library' is lacking in leadership, yet another report finds] {{Webarchive |url=https://web.archive.org/web/20201011043431/https://www.washingtonpost.com/entertainment/museums/americas-national-library-is-behind-the-digital-curve-a-new-report-finds/2015/03/31/fad54c3a-d3fd-11e4-a62f-ee745911a4ff_story.html |date=October 11, 2020 }} by Peggy McGlone, ''The Washington Post'', March 31, 2015.</ref>

When Billington announced his plans to retire in 2015, commentator [[George Weigel]] described the Library of Congress as "one of the last refuges in Washington of serious bipartisanship and calm, considered conversation", and "one of the world's greatest cultural centers".<ref>{{Cite web |title=America's Next 'Minister of Culture': Don't Politicize the Appointment |first=George|last=Weigel|website=[[National Review]] |date=June 12, 2015 |url=http://www.nationalreview.com/article/419664/americas-next-minister-culture-dont-politicize-appointment |access-date=September 22, 2015 |archive-date=September 23, 2015 |archive-url=https://web.archive.org/web/20150923090036/http://www.nationalreview.com/article/419664/americas-next-minister-culture-dont-politicize-appointment |url-status=dead }}</ref>

=== 2016–2025 Hayden leadership ===

Appointed in 2016 by President [[Barack Obama]], [[Carla Hayden|Carla D. Hayden]] was sworn in as the fourteenth librarian of Congress on September 14, 2016. She is the first professional librarian to hold the post since 1974,<ref name="ALA-Hayden-LibrarianOfCongress-2016">{{cite news |last1=Hines |first1=Shawnda |date=July 16, 2016 |title=Dr. Carla Hayden to serve as the next Librarian of Congress |url=https://www.ala.org/news/2016/07/dr-carla-hayden-serve-next-librarian-congress |url-status=live |archive-url=https://web.archive.org/web/20181230122800/http://www.ala.org/news/press-releases/2016/07/dr-carla-hayden-serve-next-librarian-congress |archive-date=December 30, 2018 |access-date=February 25, 2025 |work=American Library Association |format=Press release}}</ref> holding a Ph.D. in [[Library and information science|library science]] from the [[University of Chicago]]. She was the [[Chief executive officer|CEO]] of [[Enoch Pratt Free Library]] in [[Baltimore]], Maryland, from 1993 until 2016, and president of the [[American Library Association]] (ALA) from 2003 to 2004.<ref name=BaltimoreSun-EnochPratt-ActingCEO-2016>{{cite news|title=Enoch Pratt library names Gordon Krabbe acting CEO|url=http://www.baltimoresun.com/entertainment/arts/bal-enoch-pratt-library-names-acting-ceo-20160811-story.html|work=The Baltimore Sun|date=August 11, 2016}}</ref><ref name="ALA-PastPresidents-2011">{{cite news |date= |title=ALA Past Presidents |url=https://www.ala.org/aboutala/history/past |archive-url= |archive-date= |access-date=February 25, 2025 |work=American Library Association}}</ref><ref name=Jet-ALAPresident-2002>{{cite news|title=Carla Hayden Elected New American Library Association President|url=https://books.google.com/books?id=LMMDAAAAMBAJ&q=carla+hayden|work=[[Jet (magazine)|Jet]]|publisher=Johnson Publishing Company|date=May 27, 2002|language=en}}</ref> She also is the first woman and the first African American to hold the position.<ref>{{cite web |url=https://www.washingtonpost.com/news/arts-and-entertainment/wp/2016/07/13/carla-hayden-confirmed-as-14th-librarian-of-congress/ |title=Carla Hayden confirmed as 14th librarian of Congress |first=Peggy |last=McGlone |date=July 13, 2016 |website=Washingtonpost.com |access-date=May 5, 2017 |archive-date=March 2, 2017 |archive-url=https://web.archive.org/web/20170302014722/https://www.washingtonpost.com/news/arts-and-entertainment/wp/2016/07/13/carla-hayden-confirmed-as-14th-librarian-of-congress/ |url-status=live }}</ref><ref>{{cite web |url=https://americanlibrariesmagazine.org/latest-links/carla-hayden-sworn-september-14/ |title=Carla Hayden to be sworn in on September 14 – American Libraries Magazine |website=Americanlibrariesmagazine.org |access-date=May 5, 2017 |url-status=dead |archive-url=https://web.archive.org/web/20170510073226/https://americanlibrariesmagazine.org/latest-links/carla-hayden-sworn-september-14/ |archive-date=May 10, 2017}}</ref> She continued the work of digitizing as much as possible of the collection and of expanding electronic access to the collection. She initiated programs to modernize the library, expand access from rural areas, and expanding the infrastructure and technological capacity of the library and 
assessment of her leadership of the library by the community reflects her expressed goals. The [[Association of Research Libraries]] noted Hayden's transformation of the library "into a more open, accessible, and celebrated U.S. institution, while reaffirming its role as the people’s library".<ref>{{cite web | publisher= Association of Research Libraries. |url=https://www.arl.org/news/arl-comments-on-the-dismissal-of-dr-carla-hayden-from-the-library-of-congress/ |title=ARL Comments on the Dismissal of Dr. Carla Hayden from the Library of Congress|date=May 9, 2025|access-date=10 May 2025}}</ref> The [[American Library Association]] characterized Hayden as a "wise and faithful steward of the Library of Congress – the library she has called our 'national treasure'".<ref>{{cite web|first=Cindy |last=Hohl|url=https://www.ala.org/news/2025/05/ALA-praises-service-dr-carla-hayden-decries-dismissal |title=ALA praises service of Dr. Carla Hayden, decries "unjust dismissal"|publisher=American Library Association|date=May 9, 2025|access-date=May 10, 2025}}</ref>

[[File:Dr. Hayden and Ms. Lynda Carter in Wonder Women poses.jpg|300px|thumb|Librarian Carla Hayden (left) and [[Lynda Carter]] participating in the June 2017 "Library of Awesome" event at the United States Library of Congress that celebrated the role of comics and graphic novels in promoting literacy, as they strike the typical pose of [[Wonder Woman]]]]
In 2017, Hayden announced the Librarian-in-Residence program, which aims to support the future generation of librarians by giving them the opportunity to gain work experience in five different areas of librarianship, including: Acquisitions/Collection Development, Cataloging/Metadata, and Collection Preservation.<ref>{{Cite news |url=https://www.loc.gov/librarians/librarians-in-residence/ |title=Librarians-in-Residence – |work=The Library of Congress |access-date=November 7, 2017 |language=en |archive-date=November 7, 2017 |archive-url=https://web.archive.org/web/20171107111935/https://www.loc.gov/librarians/librarians-in-residence/ |url-status=live }}</ref>

On January 6, 2021, at 1:11&nbsp;pm EST, the Library's [[James Madison Memorial Building|Madison Building]] and the [[Cannon House Office Building]] were the first buildings in the Capitol Complex to be ordered to evacuate as rioters breached security perimeters before [[January 6 United States Capitol attack|storming the Capitol building]].<ref>{{cite news |last1=Budryk |first1=Zack |last2=Lillis |first2=Mike |last3=Coleman |first3=Justine |date=January 6, 2021 |title=Capitol placed on lockdown, buildings evacuated amid protests |work=The Hill |url=https://thehill.com/homenews/house/532925-capitol-police-evacuate-madison-cannon-buildings |access-date=January 8, 2021 |archive-date=February 22, 2021 |archive-url=https://web.archive.org/web/20210222052805/https://thehill.com/homenews/house/532925-capitol-police-evacuate-madison-cannon-buildings |url-status=live }}</ref><ref>{{cite news |date=January 8, 2021 |title=Timeline: How a Trump mob stormed the US Capitol, forcing Washington into lockdown |newspaper=USA Today |url=https://www.usatoday.com/in-depth/news/2021/01/06/dc-protests-capitol-riot-trump-supporters-electoral-college-stolen-election/6568305002/ |access-date=January 8, 2021 |archive-date=January 24, 2021 |archive-url=https://web.archive.org/web/20210124224457/https://www.usatoday.com/in-depth/news/2021/01/06/dc-protests-capitol-riot-trump-supporters-electoral-college-stolen-election/6568305002/ |url-status=live }}</ref><ref>{{Cite tweet |user=sarahnferris |number=1346883107501314048 |date=January 6, 2021 |title=WOW Hill staff just got this alert "Madison: EVACUATE. Proceed to your designated assembly area. USCP"}}</ref> Hayden clarified two days later that rioters did not breach any of the Library buildings or collections and all staff members were safely evacuated.<ref>{{Cite journal |last=Hayden |first=Carla |date=January 8, 2021 |title=Thoughts on this week's unrest |url=https://www.loc.gov/staff/gazette/uploads/2021/01/01_Gazette_010821_web.pdf |journal=The Library of Congress Gazette |volume=32 |access-date=May 17, 2021 |archive-date=May 13, 2021 |archive-url=https://web.archive.org/web/20210513220742/https://www.loc.gov/staff/gazette/uploads/2021/01/01_Gazette_010821_web.pdf |url-status=live }}</ref>

On February 14, 2023, Hayden announced that the [[Lilly Endowment]] gifted the library with $2.5&nbsp;million as a five-year grant to "launch programs that foster greater understanding of religious cultures in Africa, Central Asia, and the Middle East".<ref name=":0">{{Cite web |last=Banks |first=Adelle M. |date=February 14, 2023 |title=Library of Congress to highlight Muslim slave and scholar with $2.5 million grant |url=https://religionnews.com/2023/02/14/library-of-congress-to-highlight-muslim-slave-and-scholar-with-2-5-million-grant/ |access-date=March 6, 2023 |website=Religion News Service |language=en-US}}</ref> The Library plans to leverage the donation in these areas:

* Produce a book and a film about [[Omar ibn Said]]
* Provide public access to "programs that enhance knowledge about faiths practiced in the regions, including Indigenous African religious traditions, Judaism, Christianity, Islam, and their influence on daily life."<ref name=":0"/>

On May 8, 2025, two days after Hayden had given testimony to the [[United States Senate Committee on Appropriations|Senate Committee on Appropriations]] and the [[United States House Committee on House Administration|Committee on House Administration]],<ref>{{cite web |title=A Review of the Fiscal Year 2026 Budget Requests for the Library of Congress and the Architect of the Capitol |url=https://www.appropriations.senate.gov/hearings/a-review-of-the-fiscal-year-2026-budget-requests-for-the-library-of-congress-and-the-architect-of-the-capitol |website=www.appropriations.senate.gov |publisher=United States Senate Committee on Appropriations |access-date=May 10, 2025 |language=en}}<br />{{cite web |last1=Hayden |first1=Carla |title=Statement of Carla Hayden The Librarian of Congress Before the Subcommittee on the Legislative Branch Committee on Appropriations United States Senate|date=May 6, 2025 |url=https://www.appropriations.senate.gov/imo/media/doc/carla_hayden_testimony_5625.pdf |access-date= May 10, 2025}}</ref><ref>{{cite web |title=Full Committee Hearing: "Oversight of the Operations of the Library of Congress"|url=https://cha.house.gov/hearings?ID=F239CAED-BBE2-4239-9ADC-E15605407EAA |website=United States Committee on House Administration |access-date=10 May 2025 |language=en |date=6 May 2025}}</ref> via email and without any explanation, she was abruptly fired by [[Donald Trump|President Trump]].<ref>{{Cite web |last1=Seung |first1=Min Kim |last2=Miller |first2=Zeke |last3=Mascaro |first3=Lisa |date=2025-05-09 |title=President Trump fires Librarian of Congress Carla Hayden |url=https://apnews.com/article/donald-trump-library-of-congress-carla-hayden-20a1862ce6d2e0d51a84a37b264ce2ef |access-date=May 10, 2025 |website=AP News |language=en}}</ref><ref>{{cite web |date=10 May 2025 |title=President Trump fires Librarian of Congress Carla Hayden |url=https://apnews.com/article/donald-trump-library-of-congress-carla-hayden-20a1862ce6d2e0d51a84a37b264ce2ef |access-date=May 10, 2025 |work=Associated Press}}</ref> ''[[Publishers' Weekly]]'' characterized Hayden's termination as the "latest blow to professional research and the literary and arts community."<ref name=opdebeek>{{cite news|first=Nathalie |last=op de Beeck|url=https://www.publishersweekly.com/pw/by-topic/industry-news/libraries/article/97731-librarian-of-congress-carla-hayden-fired-by-white-house.html |title=Librarian of Congress Carla Hayden Fired by White House|work=Publishers' Weekly|date=May 9, 2025|access-date=May 10, 2025}}</ref><ref>Italie, Hillel, ''[https://apnews.com/article/library-of-congress-card-history-librarian-firings-83d9e862a68832d8076773a7eb16114f Firing, hiring and a mystery: The 225-year-old Library of Congress has never had a moment like this]'', The Associated Press, May 15, 2025</ref>

No replacement of Hayden has been nominated. Principal Deputy Librarian [[Robert Newlen]],<ref name="TMK-CJ-CK 2025">{{cite news |last1=Tully-McManus |first1=Katherine |last2=Carney |first2=Jordain |last3=Cheney |first3=Kyle |author-link3=Kyle Cheney (journalist) |title=Hill leaders question Trump's attempted Library of Congress takeover |url=https://www.politico.com/live-updates/2025/05/12/congress/donald-trump-library-of-congress-fight-00342326 |access-date=May 14, 2025 |work=[[Politico]] |date=May 12, 2025}}</ref> who would have served as interim librarian was fired and Trump named Deputy Attorney General [[Todd Blanche]] as acting librarian of Congress and later fired the deputy librarian and copyright office director (Perlmutter and Newlen), appointing senior DOJ officials Brian Nieves and Paul Perkins as respectively, for the interim. This has been interpreted as an attack on the separation of powers.<ref>Kim, Seung Min, ''[https://apnews.com/article/donald-trump-library-of-congress-capitol-hill-cd401629dbec487f778a8beb13761f65 Donald Trump’s Library of Congress fight is really about the separation of powers]'', [[Associated Press]], May 16, 2025</ref> Perlmutter has sued to dispute the legality of the dismissal,<ref>Smith, Dylan, ''[https://www.digitalmusicnews.com/2025/05/23/shira-perlmutter-lawsuit/ Fired Copyright Office Head Shira Perlmutter Sues Trump Administration Over ‘Blatantly Unlawful’ Dismissal]'', Digital Music News, May 23, 2025</ref> as the Register is appointed by, and responsible to, the [[Librarian of Congress]].

== Holdings ==
[[File:Great Hall, Library of Congress Thomas Jefferson Building, Washington, D.C. View of first and second floors, with Minerva mosaic in background. (LOC).jpg|thumb|The extravagant design of the Great Hall is an example of [[Beaux-Arts architecture]].]]
[[File:Library of Congress Great Hall angle.jpg|thumb|alt=photograph of the Great Hall in the Thomas Jefferson building|The Great Hall interior, looking toward the ceiling|upright]]
[[File:Library Congress October 2016-1.jpg|thumb|Ceiling of the Great Hall]]

The collections of the Library of Congress include more than 32 million catalogued books and other print materials in 470 languages; more than 61&nbsp;million manuscripts; the largest rare book collection<ref>{{cite web |url=https://www.loc.gov/rr/rarebook/ |title=Rare Book and Special Collections Reading Room (Library of Congress) |website=Loc.gov |access-date=May 5, 2017 |archive-date=May 6, 2017 |archive-url=https://web.archive.org/web/20170506042254/http://www.loc.gov/rr/rarebook/ |url-status=live }}</ref> in North America, including the rough draft of the [[United States Declaration of Independence|Declaration of Independence]], a [[Gutenberg Bible]] (originating from the [[Saint Blaise Abbey, Black Forest]]—one of only three perfect [[vellum]] copies known to exist);<ref>{{cite web |url=http://www.approvedarticles.com/Article/Gutenberg-s-Bibles--Where-to-Find-Them/1088 |title=Gutenberg's Bibles— Where to Find Them |work=ApprovedArticles.com |first=Brett |last=Nga |access-date=April 1, 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080706031919/http://www.approvedarticles.com/Article/Gutenberg-s-Bibles--Where-to-Find-Them/1088 |archive-date=July 6, 2008}}</ref><ref>{{cite web |url=http://www.octavo.com/editions/gtnbbl/index.html |archive-url=https://web.archive.org/web/20041127190224/http://www.octavo.com/editions/gtnbbl/index.html |url-status=dead |archive-date=November 27, 2004 |title=Octavo Editions: Gutenberg Bible |work=octavo.com}}</ref><ref>{{cite web |url=https://www.loc.gov/rr/rarebook/guide/europe.html |title=Europe (Library of Congress Rare Books and Special Collections: An Illustrated Guide) |website=Loc.gov |access-date=May 5, 2017 |archive-date=April 7, 2020 |archive-url=https://web.archive.org/web/20200407015658/https://www.loc.gov/rr/rarebook/guide/europe.html |url-status=live }}</ref><!-- ANONS, PLEASE READ THE LINK COMPLETELY before changing it to '3': "A fourth and final perfect vellum copy of the Bible is in Goettigen, Germany's Universitaetsbibliothek." --> over 1 million [[U.S. government]] publications; 1 million issues of world newspapers spanning the past three centuries; 33,000 bound newspaper volumes; 500,000 [[microfilm]] reels; U.S. and foreign comic books—over 12,000 titles in all, totaling more than 140,000 issues;<ref>{{cite web |date=August 27, 2020 |url=https://www.loc.gov/rr/news/coll/049.html |title=Comic Book Collection |publisher=The Library of Congress |access-date=August 27, 2020 |archive-date=August 5, 2019 |archive-url=https://web.archive.org/web/20190805043031/http://www.loc.gov/rr/news/coll/049.html |url-status=live }}</ref> 1.9&nbsp;million moving images (as of 2020); 5.3&nbsp;million maps; 6 million works of [[sheet music]]; 3 million [[sound recording]]s; more than 14.7&nbsp;million prints and photographic images including fine and popular art pieces and architectural drawings;<ref>{{Citation |title=Annual Report of the Librarian of Congress |publisher=Library of Congress |year=2009 |url=https://www.loc.gov/about/reports/annualreports/fy2009.pdf |access-date=December 30, 2017 |archive-date=April 5, 2017 |archive-url=https://web.archive.org/web/20170405065850/https://www.loc.gov/about/reports/annualreports/fy2009.pdf/ |url-status=live }}</ref> the [[Betts Stradivarius]]; and the [[List of Stradivarius instruments#Violas|Cassavetti Stradivarius]].

The library developed a system of book classification called [[Library of Congress Classification]] (LCC), which is used by most U.S. research and [[university library|university libraries]].

The library serves as a legal repository for [[copyright]] protection and [[copyright registration]], and as the base for the [[United States Copyright Office]]. Regardless of whether they register their copyright, all publishers are required to submit two complete copies of their published works to the library—this requirement is known as ''mandatory deposit''.<ref>{{cite web |url=http://www.copyright.gov/help/faq/mandatory_deposit.html |title=Mandatory Deposit |publisher=Copyright.gov |access-date=August 8, 2006 |archive-date=July 26, 2006 |archive-url=https://web.archive.org/web/20060726211432/http://www.copyright.gov/help/faq/mandatory_deposit.html |url-status=live }}</ref> Nearly 15,000 new items published in the U.S. arrive every business day at the library. Contrary to popular belief, however, the library does not retain all of these works in its permanent collection, although it does add an average of 12,000 items per day.<ref name="Fascinating Facts"/> Rejected items are used in trades with other libraries around the world, distributed to federal agencies, or donated to schools, communities, and other organizations within the United States.<ref name="Fascinating Facts"/>

As is true of many [[Legal deposit|similar libraries]], the Library of Congress retains copies of every publication in the English language that is deemed significant.
The Library of Congress states that its collection fills about {{cvt|838|mi}} of bookshelves and holds more than 167 million items with over 39&nbsp;million books and other print materials.<ref name="FFStats"/> A 2000 study by information scientists [[Peter Lyman]] and [[Hal Varian]] suggested that the amount of uncompressed [[Text file|textual data]] represented by the 26 million books then in the collection was 10 [[terabyte]]s.<ref>{{cite web |url=http://www2.sims.berkeley.edu/research/projects/how-much-info/how-much-info.pdf#page=110 |first1=Peter |last1=Lyman |first2=Hal R. |last2=Varian |title=How Much Information? |access-date=October 14, 2013 |date=October 18, 2000 |archive-date=August 16, 2011 |archive-url=https://web.archive.org/web/20110816181442/http://www2.sims.berkeley.edu/research/projects/how-much-info/how-much-info.pdf#page=110 |url-status=dead|quote=10 Terabytes: The printed collection of the US Library of Congress}}</ref>

The library also administers the [[National Library Service for the Blind and Print Disabled|National Library Service for the Blind and Physically Handicapped]], an audio book and [[braille]] library program provided to more than 766,000 Americans.

===Digital===
The library's first digitization project, [[American Memory]], was launched in 1990, and was initially planned to choose 160 million objects from its collection to make digitally available on [[LaserDisc]]s and [[CDs]], which were distributed to schools and libraries.

After realizing that this plan would be too expensive and inefficient, and with the rise of the Internet, the library decided to instead make digitized material available over the Internet. This project was made official in the National Digital Library Program (NDLP), created in October 1994. By 1999, the NDLP had succeeded in digitizing over 5 million objects and had a budget of $12&nbsp;million. The library has kept the "American Memory" name for its public domain website, which today contains 15&nbsp;million digital objects, comprising over 7 [[petabyte]]s of data.<ref name=":1">{{Cite web |url=https://nplusonemag.com/online-only/online-only/the-library-of-last-resort/ |title=The Library of Last Resort |last=Chayka |first=Kyle |date=July 14, 2016 |publisher=n+1 Magazine |language=en-US |access-date=July 19, 2016 |archive-url=https://web.archive.org/web/20180119235106/https://nplusonemag.com/online-only/online-only/the-library-of-last-resort/ |archive-date=January 19, 2018 |url-status=dead}}</ref>

American Memory is a source for [[public domain]] image resources, as well as audio, video, and archived Web content.

Nearly all of the lists of holdings, the ''catalogs'' of the library, can be consulted directly on its website. Librarians all over the world consult these catalogs, through the Web or through other media better suited to their needs, when they need to catalog for their collection a book published in the United States. They use the [[Library of Congress Control Number]] to make sure of the exact identity of the book.

Digital images are also available at [[Snapshots of the Past]], which provides archival prints.<ref>{{Cite web |url=http://www.snapshotsofthepast.com/about-us |title=About Us |website=Snapshots of the Past |access-date=April 26, 2016 |archive-date=May 14, 2016 |archive-url=https://web.archive.org/web/20160514000831/http://www.snapshotsofthepast.com/about-us |url-status=dead}}</ref>
The library has a budget of $6–8&nbsp;million each year for digitization, meaning that not all works can be digitized. It makes determinations about what objects to prioritize based on what is especially important to Congress or potentially interesting for the public. The 15 million digitized items represent less than 10% of the library's total 160-million-item collection.

The library has chosen not to participate in other digital library projects such as [[Google Books]] and the [[Digital Public Library of America]], although it has supported the [[Internet Archive]] project.<ref name=":1"/>

===Congressional===
In 1995, the Library of Congress established [[THOMAS]], an online archive of the proceedings of the [[United States Congress]], which included the full text of proposed legislation, bill summaries, and statuses, ''[[Congressional Record]]'' text, and an index of the ''[[Congressional Record]]''. In 2005 and again in 2010, the THOMAS system received major updates. A migration to a more modernized Web system, [[Congress.gov]], began in 2012, and the THOMAS system was retired in 2016.<ref>David Gewirtz, [https://www.zdnet.com/article/thomas-gov-an-exclusive-inside-look-at-the-retirement-and-transition-of-a-classic-web-1-0/ So long, Thomas.gov: Inside the retirement of a classic Web 1.0 application] {{Webarchive |url=https://web.archive.org/web/20160505012419/http://www.zdnet.com/article/thomas-gov-an-exclusive-inside-look-at-the-retirement-and-transition-of-a-classic-web-1-0/ |date=May 5, 2016 }}, ZDNet (May 4, 2016).</ref> Congress.gov is a joint project of the Library of Congress, the House, the Senate, and the [[Government Publishing Office]].<ref>{{cite web|first= Adam|last= Mazmanian|url=https://fcw.com/articles/2016/04/28/thomas-loc-retired.aspx |title=Library of Congress to retire Thomas|archive-url=https://web.archive.org/web/20160607113335/https://fcw.com/articles/2016/04/28/thomas-loc-retired.aspx |archive-date=June 7, 2016 |work =[[Federal Computer Week]]|date =April 28, 2016}}</ref>

==Buildings==
[[File:Thomas Jefferson Building Aerial by Carol M. Highsmith.jpg|thumb|alt=Aerial photograph of the Thomas Jefferson Building by Carol M. Highsmith|The [[Thomas Jefferson Building]] and part of the Adams Building (on the upper right) next to the [[United States Supreme Court Building|Supreme Court Building]] (upper left) on [[Capitol Hill]]]]
The Library of Congress is physically housed in three buildings on [[Capitol Hill]] and a conservation center in rural [[Virginia]]. The library's Capitol Hill buildings are all connected by underground passageways, so that a library user need pass through security only once in a single visit. The library also has off-site storage facilities in [[Maryland]] for less commonly requested materials.

===Thomas Jefferson Building===
{{Main|Thomas Jefferson Building}}
The [[Thomas Jefferson Building]] is located between [[Independence Avenue (Washington, D.C.)|Independence Avenue]] and East Capitol Street on First Street SE. Construction began in 1890 with granite supplied by [[New England Granite Works]], owned by [[James G. Batterson]].<ref>{{cite news |title=Death List of a Day |url=https://timesmachine.nytimes.com/timesmachine/1901/09/19/102627154.pdf?pdf_redirect=true&ip=0 |access-date=19 September 2024 |agency=The New York Times |date=19 September 1901}}</ref> The building opened in 1897 as the main building of the library and is the oldest of the three buildings. Known originally as the Library of Congress Building or Main Building, it took its present name on June 13, 1980.<ref>{{Cite book |url=https://www.loc.gov/loc/walls/ |title=On These Walls: Inscriptions and Quotations in the Buildings of the Library of Congress |last=Cole |first=John |publisher=Scala Arts Publishers Inc. |year=2008 |isbn=978-1857595451 |chapter=The Thomas Jefferson Building |access-date=April 23, 2018 |chapter-url=https://www.loc.gov/loc/walls/jeff1.html |archive-date=July 20, 2018 |archive-url=https://web.archive.org/web/20180720192748/http://www.loc.gov/loc/walls/ |url-status=live }}</ref>

===John Adams Building===
{{Main|John Adams Building}}
[[File:John Adams Building (31274182293).jpg|thumb|The [[John Adams Building]]]]
The [[John Adams Building]] is located between Independence Avenue and East Capitol Street on 2nd Street SE, the block adjacent to the Jefferson Building. The building was originally known as The Annex to the Main Building, which had run out of space. It opened its doors to the public on January 3, 1939.<ref>{{Cite book |url=https://www.loc.gov/loc/walls/ |title=On These Walls: Inscriptions and Quotations in the Buildings of the Library of Congress |last=Cole |first=John |publisher=Scala Arts Publishers Inc. |year=2008 |isbn=978-1857595451 |chapter=The John Adams Building |access-date=April 23, 2018 |chapter-url=https://www.loc.gov/loc/walls/adams.html |archive-date=July 20, 2018 |archive-url=https://web.archive.org/web/20180720192748/http://www.loc.gov/loc/walls/ |url-status=live }}</ref> Initially, it also housed the U.S. Copyright Office which moved to the Madison building in the 1970s.

===James Madison Memorial Building===
{{Main|James Madison Memorial Building}}
[[File:Exterior view, from corner of Independence Ave. and 2nd St. Library of Congress James Madison Building, Washington, D.C. LCCN2007687169.jpg|thumb|alt=northeast photograph of Madison Building by Carol M. Highsmith|The [[James Madison Memorial Building]]]]
The James Madison Memorial Building is located between First and Second Streets on Independence Avenue SE. The building was constructed from 1971 to 1976, and serves as the official memorial to [[James Madison]], a [[Founding Father of the United States|Founding Father]] and the fourth President of the United States<ref>{{Cite book |url=https://www.loc.gov/loc/walls/ |title=On These Walls: Inscriptions and Quotations in the Buildings of the Library of Congress |last=Cole |first=John |publisher=Scala Arts Publishers Inc. |year=2008 |isbn=978-1857595451 |chapter=The James Madison Memorial Building |access-date=April 23, 2018 |chapter-url=https://www.loc.gov/loc/walls/madison.html |archive-date=July 20, 2018 |archive-url=https://web.archive.org/web/20180720192748/http://www.loc.gov/loc/walls/ |url-status=live }}</ref>

The Madison Building is also home to the [[United States Copyright Office]] and to the Mary Pickford Theater, the "motion picture and television reading room" of the Library of Congress. The theater hosts regular free screenings of classic and contemporary movies and television shows.<ref>{{Cite web |url=https://www.loc.gov/rr/mopic/pickford/ |title=Mary Pickford Theater Film Schedule |website=Moving Image Research Center |publisher=Library of Congress |access-date=April 23, 2018 |archive-date=April 23, 2018 |archive-url=https://web.archive.org/web/20180423170215/http://www.loc.gov/rr/mopic/pickford/ |url-status=live }}</ref>

===Packard Campus for Audio-Visual Conservation===
{{Main|National Audio-Visual Conservation Center}}
[[File:Packard-campus-library-of-c.jpg|thumb|alt=photograph of the National Audio-Visual Conservation Center Packard Campus in Culpeper, Virginia|The [[National Audio-Visual Conservation Center]] in [[Culpeper, Virginia]]]]
Founded in 2007 and located in [[Culpeper, Virginia]] in [[Northern Virginia]], the [[National Audio-Visual Conservation Center]] is the Library of Congress's newest building.<ref>{{cite web |url=https://www.loc.gov/avconservation/packard/ |title=The Packard Campus – A/V Conservation (Library of Congress) |website=Loc.gov |access-date=May 5, 2017 |archive-date=May 6, 2017 |archive-url=https://web.archive.org/web/20170506162454/http://www.loc.gov/avconservation/packard/ |url-status=live }}</ref> It was constructed out of a former [[Federal Reserve System|Federal Reserve]] storage center and [[Cold War]] bunker. The campus is designed to act as a single site to store all of the library's movie, television, and sound collections. It is named in honor of [[David Woodley Packard]], whose [[Packard Humanities Institute]] oversaw the design and construction of the facility. The centerpiece of the complex is a reproduction [[Art Deco]] movie theater that presents free movie screenings to the public on a semi-weekly basis.<ref>{{cite web |url=https://www.loc.gov/loc/events/#eventlist9 |title=Library of Congress events listing |publisher=Loc.gov |access-date=November 4, 2012 |archive-date=November 2, 2012 |archive-url=https://web.archive.org/web/20121102124044/http://www.loc.gov/loc/events/#eventlist9 |url-status=live }}</ref>

==Copyright Act==
{{Main|Digital Millennium Copyright Act#Anti-circumvention exemptions|l1=Digital Millennium Copyright Act}}
{{See also|Librarian of Congress|Register of Copyrights}}

The Library of Congress, through both the librarian of Congress and the register of copyrights, is responsible for authorizing exceptions to Section 1201 of [[Title 17 of the United States Code]] as part of the Digital Millennium Copyright Act. This process is done every three years, with the register receiving proposals from the public and acting as an advisor to the librarian, who issues a ruling on what is exempt. After three years have passed, the ruling is no longer valid and a new ruling on exemptions must be made.<ref>{{cite web |url=http://www.copyright.gov/1201/ |title=Section 1201: Exemptions to Prohibition Against Circumvention of Technological Measures Protecting Copyrighted Works |work=United States Copyright Office |year=2013 |access-date=July 26, 2014 |archive-date=August 6, 2009 |archive-url=https://web.archive.org/web/20090806213422/http://www.copyright.gov/1201/ |url-status=live }}</ref><ref>{{cite press release |url=https://www.loc.gov/today/pr/2013/13-041.html |title=Statement Regarding White House Response to 1201 Rulemaking |publisher=Library of Congress |year=2013 |access-date=July 26, 2014 |archive-date=August 2, 2014 |archive-url=https://web.archive.org/web/20140802091904/http://www.loc.gov/today/pr/2013/13-041.html |url-status=live }}</ref>

==Access==
The library is open for academic research to anyone with a Reader Identification Card. One may not remove library items from the reading rooms or the library buildings. Most of the library's general collection of books and journals are in the closed stacks of the Jefferson and Adams Buildings; specialized collections of books and other materials are in closed stacks in all three main library buildings, or are stored off-site. Access to the closed stacks is not permitted under any circumstances, except to authorized library staff, and occasionally, to dignitaries. Only the reading room reference collections are on open shelves.<ref>{{Cite web |title=Using the Library's Collections (Research and Reference Services, Library of Congress) |url=https://www.loc.gov/rr/useofcollections.html |access-date=February 23, 2022 |website=loc.gov |archive-date=February 23, 2022 |archive-url=https://web.archive.org/web/20220223042411/https://www.loc.gov/rr/useofcollections.html |url-status=live }}</ref>

Since 1902, American libraries have been able to request books and other items through [[interlibrary loan]] from the Library of Congress if these items are not readily available elsewhere. Through this system, the Library of Congress has served as a "library of last resort", according to [[Herbert Putnam]], the [[Librarian of Congress]] from 1899 to 1939.<ref name="interlibrary loan"/> The Library of Congress lends books to other libraries with the stipulation that they be used only inside the borrowing library.<ref>{{cite web |url=https://www.loc.gov/rr/loan/loanweb1.html |title=Subpage Title (Interlibrary Loan, Library of Congress) |publisher=Loc.gov |date=July 14, 2010 |access-date=November 4, 2012 |archive-date=November 4, 2012 |archive-url=https://web.archive.org/web/20121104023748/http://www.loc.gov/rr/loan/loanweb1.html |url-status=live }}</ref> In 2017, the Library of Congress began development on a reader's card for children under the age of sixteen.<ref>{{Cite web |date=2017-10-26 |title=Adam Coffey, 8, of San Clemente Convinces Library of Congress to Initiate Children's Program |url=https://www.picketfencemedia.com/sanclementetimes/eye-on-sc/adam-coffey-8-of-san-clemente-convinces-library-of-congress-to-initiate-children-s-program/article_ff216e47-20ec-59e8-982f-6ad856ea1123.html |access-date=2024-04-13 |website=Picket Fence Media |language=en}}</ref>

==Standards==
In addition to its library services, the Library of Congress is actively involved in various standard activities in areas related to bibliographical and search and retrieval standards. Areas of work include [[MARC standards]], [[Metadata Encoding and Transmission Standard]] (METS), [[Metadata Object Description Schema]] (MODS), [[Z39.50]] and [[Search/Retrieve Web Service]] (SRW), and [[Search/Retrieve via URL]] (SRU).<ref>{{Cite web |url=https://www.loc.gov/standards/ |title=Standards at the Library of Congress |website=Loc.gov |access-date=May 5, 2017 |archive-date=May 4, 2017 |archive-url=https://web.archive.org/web/20170504211816/https://www.loc.gov/standards/ |url-status=live }}</ref> The [[Law Library of Congress]] "seeks to further legal scholarship by providing opportunities for scholars and practitioners to conduct significant legal research. Individuals are invited to apply for projects which would further the multi-faceted mission of the law library in serving the U.S. Congress, other governmental agencies, and the public."<ref>{{cite web |title= Opportunities |website= Law Library of Congress |publisher= loc.gov |url= https://www.loc.gov/research-centers/law-library-of-congress/about-this-research-center/opportunities/ }}</ref>

==Annual events==
*[[Fellows in American Letters of the Library of Congress]]
*[[Gershwin Prize]] for Popular Song
*[[Library of Congress Prize for American Fiction]]
*[[Minor American Revolution holidays#Founder's Day|Founder's Day]] Celebration
*[[National Audio-Visual Conservation Center#Mostly Lost Film Identification Workshop|Mostly Lost Film Identification Workshop]]
*[[National Book Festival]]

==Notable personnel==
{{see also|Librarian of Congress}}
*[[Henriette Avram]]: Developed the MARC format (Machine Readable Cataloging), the international data standard for bibliographic and holdings information in libraries. 
*[[John Y. Cole]]: founder of the [[Center for the Book]] and first historian of the Library of Congress.
*[[Cecil Hobbs]]: American scholar of Southeast Asian history, head of the Southern Asia Section of the Orientalia (now Asian) Division of the Library of Congress, and a major contributor to scholarship on Asia and the development of South East Asian coverage in American library collections.<ref>{{cite journal |first=Warren |last=Tsuneishi |date=May 1992 |title=Obituary: Cecil Hobbs (1907–1991) |journal=[[Journal of Asian Studies]] |volume=51 |issue=2 |pages=472–473 |doi=10.1017/s0021911800041607 |doi-access=free}}</ref>
*[[Julius C. Jefferson Jr.]], head of the [[Congressional Research Service]], president of the [[American Library Association]] (2020–2021), president of the [[Freedom to Read Foundation]] (2013–2016).

==See also==
{{Portal|United States}}

{{columns-list|colwidth=20em|
*[[Architecture of Washington, D.C.]]
*[[Documents Expediting Project]]
*[[Federal Research Division]]
*[[Feleky Collection]]
*[[Law Library of Congress]]
*[[Library of Congress Classification]]
*[[Library of Congress Country Studies]]
*[[Library of Congress Living Legend]]
*[[Library of Congress Subject Headings]]
*[[Minerva Initiative]]
*[[National Digital Library Program]] (NDLP)
*[[National Film Registry]]
*[[National Recording Registry]]
*[[National Archives and Records Administration]]
*[[United States Senate Library]]
}}

== Explanatory notes ==
{{Notelist}}

==References==
{{Reflist|30em}}

===Architecture===
*Cole, John Y. and Henry Hope Reed. ''The Library of Congress: The Art and Architecture of the Thomas Jefferson Building'' (1998) [https://www.amazon.com/Library-Congress-Architecture-Jefferson-Building/dp/0393045633/ excerpt and text search]
*Small, Herbert, and Henry Hope Reed. ''The Library of Congress: Its Architecture and Decoration'' (1983)

==Further reading==
*{{cite journal |last=Aikin |first=Jane |s2cid=161865550 |year=2010 |title=Histories of the Library of Congress |journal=Libraries & the Cultural Record |volume=45 |issue=1 |pages=5–24 |doi=10.1353/lac.0.0113}}
*{{Citation |last=Anderson |first=Gillian B. |title=Putting the Experience of the World at the Nation's Command: Music at the Library of Congress, 1800–1917 |journal=Journal of the American Musicological Society |volume=42 |issue=1 |pages=108–49 |year=1989 |doi=10.2307/831419 |jstor=831419}}
*Bisbort, Alan, and Linda Barrett Osborne. ''The Nation's Library: The Library of Congress, Washington, D. C.'' (Library of Congress, 2000)
*Cole, John Young. ''Jefferson's legacy: a brief history of the Library of Congress'' (Library of Congress, 1993)
*Cole, John Young. "The library of congress becomes a world library, 1815–2005." ''Libraries & culture'' (2005) 40#3: 385–398. [https://muse.jhu.edu/article/188792/pdf in Project MUSE]
*Cope, R. L. "Management Review of the Library of Congress: The 1996 Booz Allen & Hamilton Report," ''Australian Academic & Research Libraries'' (1997) 28#1 [https://web.archive.org/web/20140226043706/http://www.questia.com/library/journal/1G1-20111506/management-review-of-the-library-of-congress-the online]
*Mearns, David Chambers. ''The Story Up to Now: The Library of Congress, 1800–1946'' (1947), detailed narrative
*Ostrowski, Carl. ''Books, Maps, and Politics: A Cultural History of the Library of Congress, 1783–1861'' (2004)
*Rosenberg, Jane Aiken. ''The Nation's Great Library: Herbert Putnam and the Library of Congress, 1899–1939'' (University of Illinois Press, 1993)
*{{cite journal |last1=Shevlin |first1=Eleanor F. |last2=Lindquist |first2=Eric N. |s2cid=161311744 |year=2010 |title=The Center for the Book and the History of the Book |journal=Libraries & the Cultural Record |volume=45 |issue=1 |pages=56–69 |doi=10.1353/lac.0.0112}}
*{{cite journal |last=Tabb |first=Winston |display-authors=etal |year=2003 |title=Library of Congress |journal=Encyclopedia of Library and Information Science |volume=3 |pages=1593–1612}}

==External links==
{{commons category|Library of Congress}}
{{scholia|topic}}
{{NIE Poster|year=1905|Library of Congress, The|Library of Congress}}
*[https://www.loc.gov/ The Library of Congress website (loc.gov)]
*[https://www.youtube.com/user/LibraryOfCongress Library of Congress channel] on YouTube
*[https://catalog.loc.gov/ Search the Library of Congress catalog]
*[https://web.archive.org/web/20061116034845/http://thefederalregister.com/b.p/department/LIBRARY_OF_CONGRESS/ Library Of Congress Meeting Notices and Rule Changes] from The Federal Register [https://web.archive.org/web/20071114080752/http://www.thefederalregister.com/rss/department/LIBRARY_OF_CONGRESS/ RSS Feed]
*[https://www.flickr.com/photos/library_of_congress/ Library of Congress photos] on [[Flickr]]
*{{Gutenberg author |id=Library+of+Congress |name=Library of Congress}}
*{{Internet Archive author |sname=Library of Congress}}
*[https://wiki.familysearch.org/en/Library_of_Congress Library of Congress] at FamilySearch Research Wiki for genealogists
*{{Cite Americana |wstitle=Congress, Library of |short=x}}
*[https://www.c-span.org/loc/ Library of Congress documentary and resources] on [[C-SPAN]]
*[https://www.loc.gov/nls/ The Library of Congress National Library Service (NLS)]
*[https://www.youtube.com/watch?v=AbfqJQ-jf7o Video: "Library of Congress in 1968 – Computer Automation"] on YouTube from Computer History Archive Project
*[http://webarchive.loc.gov/ Library of Congress Web Archives (Search by URL)]

{{Librarians of Congress}}
{{US National Libraries}}
{{CapitolComplex}}
{{USCongress}}
{{Washington DC landmarks}}
{{Legislative libraries}}
{{North America topic|prefix=National Library of |title=[[National libraries]] of North America}}
{{James Madison}}
{{Authority control}}

[[Category:Library of Congress| ]]
[[Category:1800 establishments in Washington, D.C.]]
[[Category:Agencies of the United States Congress]]
[[Category:Archives in the United States]]
[[Category:Buildings of the United States government in Washington, D.C.]]
[[Category:Capitol Hill]]
[[Category:Deposit libraries]]
[[Category:Genealogical libraries in the United States]]
[[Category:Government agencies established in 1800]]
[[Category:History museums in Washington, D.C.]]
[[Category:Independence Avenue (Washington, D.C.)]]
[[Category:Legislative libraries]]
[[Category:Libraries established in 1800]]
[[Category:Libraries in Washington, D.C.|Congress, Library of]]
[[Category:National libraries in the United States|Congress]]
[[Category:Photo archives in the United States]]
[[Category:Research libraries in the United States]]
[[Category:World Digital Library partners]]