View source for Under Secretary of Defense for Policy

{{Short description|United States government position}}
{{Use dmy dates|date=January 2022}}
{{Use American English|date = February 2019}}
{{Infobox official post
| post = Under Secretary of Defense for Policy
| insignia = Seal of the United States Department of Defense.svg
| insigniasize = 120
| insigniacaption = Seal of the Department of Defense
| flag = Flag of the U.S. Under Secretary of Defense.svg
| flagsize = 135
| flagcaption = Flag of an under secretary of defense
| department = [[United States Department of Defense]]<br/>[[Office of the Secretary of Defense]]
| reports_to = [[United States Secretary of Defense|Secretary of Defense]]<br/>[[United States Deputy Secretary of Defense|Deputy Secretary of Defense]]
| image = Elbridge A. Colby (2).jpg
| incumbent = [[Elbridge Colby]]
| incumbentsince = 15 April 2025
| acting = no
| style = Mr. Under Secretary
| appointer = The [[President of the United States|president]]<br/>with [[United States Senate|Senate]] [[advice and consent]]
| termlength = No fixed term
| first = [[Stanley Rogers Resor]]
| formation = 1978
| succession = [[United States Secretary of Defense#Succession|5th in SecDef succession]]
| deputy = Principal Deputy Under Secretary of Defense for Policy
| salary = [[Executive Schedule|Executive Schedule, level III]]
| website = {{url|policy.defense.gov}}
}}
The '''United States under secretary of defense for policy''' ('''USDP''') is a high level civilian official in the [[United States Department of Defense]]. The under secretary of defense for policy is the principal staff assistant and adviser to both the [[United States Secretary of Defense|secretary of defense]] and the [[United States Deputy Secretary of Defense|deputy secretary of defense]] for all matters concerning the formation of [[national security]] and defense policy.

The under secretary is normally appointed from civilian life by the [[President of the United States|president]] with the [[advice and consent]] of the [[United States Senate|Senate]].

==Overview==

The Office of the Under Secretary of Defense for Policy is the principal staff element of the secretary of defense in the exercise of policy development, planning, resource management, fiscal, and program evaluation responsibilities, the rank of ''Under Secretary'', the USD(P) is a Level III position within the [[Executive Schedule]].

==Reporting officials==
Officials reporting to the USD(P) include:
* Principal deputy under secretary of defense for policy

=== Strategy, plans, and capabilities ===
The '''[[assistant secretary of defense for strategy, plans, and capabilities]]''' (ASD(SPC)) is responsible for national security and defense strategy, leading the [[National Defense Strategy (United States)|National Defense Strategy]], emerging capabilities, security cooperation plans and policies, and force design and development planning.

* The '''deputy assistant secretary of defense for force development and emerging capabilities''' provides advice advancing the force development priorities of the Secretary of Defense for implementing the defense strategy, including by devising, facilitating issuance of, and overseeing DoD Component compliance with force planning and programming guidance to balance Joint Force capability, capacity, and readiness for DoD's primary defense missions and emerging security challenges.
* The '''deputy assistant secretary of defense for global partnerships''' provides advice on developing policy for security cooperation, humanitarian assistance, and international humanitarian affairs.
* The '''deputy assistant secretary of defense for plans and posture''' provides advice on developing and implementing policy, strategic guidance, and oversight of the Department of Defense’s (DoD) operational planning and overseas posture.
* The '''deputy assistant secretary of defense for strategy''' provides advice on developing the Department’s [[National Defense Strategy (United States)|national defense strategy]] and for ensuring that the Department’s program and budget decisions support implementation of the strategy.

=== International security affairs ===
The '''[[Assistant Secretary of Defense for International Security Affairs|assistant secretary of defense for international security affairs]]''' (ASD (ISA)) is responsible for international security strategy, defense policy, and oversight of security cooperation programs and foreign military sales programs relating to [[Europe]], the [[North Atlantic Treaty Organization]], [[Russia]], [[Eurasia]], the [[Middle East]], [[Africa]], and the [[Western Hemisphere]].
* The '''deputy assistant secretary of defense for African affairs''' provides advice on international security strategy, defense policy, and oversight of security cooperation programs relating to [[Sub-Sahara Africa]].
* The '''deputy assistant secretary of defense for the Middle East''' provides advice on international security strategy, defense policy, and oversight of security cooperation programs relating to the [[Middle East]] and [[North Africa]].
* The '''deputy assistant secretary of defense for Europe and NATO''' provides advice on international security strategy, defense policy, and oversight of security cooperation programs relating to [[Europe]] and [[NATO]].
* The '''deputy assistant secretary of defense for Russia, Ukraine, and Eurasia''' provides advice on international security strategy, defense policy, and oversight of security cooperation programs relating to conventional [[arms control]], [[Russia]], [[Ukraine]], [[Balkans#Western Balkans|Western Balkans]], and [[Eurasia]]n nations.
* The '''secretary of defense representative in the [[United States Permanent Representative to NATO|United States Mission to NATO]]'''.
* The '''secretary of defense representative to the [[Organization for Security and Co-operation in Europe]]'''.

=== Homeland defense and hemispheric affairs ===
The [[Assistant Secretary of Defense for Homeland Defense and Hemispheric Affairs|assistant secretary of defense for homeland defense and hemispheric affairs]] (ASD(HD&HA)) is responsible for the policy, strategy, and implementation guidance for national and global security issues across countering [[weapons of mass destruction]], [[Cyberwarfare|cyber]] operations, [[homeland defense]] activities, [[antiterrorism]], [[continuity of government]] and mission assurance, and defense support to civil authorities. The ASD(HD&HA) is also responsible for the Protected Critical Infrastructure Program (PCII), the Domestic Preparedness Support Initiative, and the Defense Critical Infrastructure Program (DCIP).
* The '''deputy assistant secretary of defense for countering weapons of mass destruction''' is responsible for the policy and guidance for [[chemical, biological, radiological, and nuclear]] protection, [[weapons of mass destruction]] [[countermeasures]], and [[counterproliferation]] and [[non-proliferation]].
* The '''deputy assistant secretary of defense for homeland defense integration and defense support of civil authorities''' is responsible for the development, coordination, and oversight of the integration and implementation of plans and policy for [[Defense Support of Civil authorities|defense support of civil authorities]] and [[civil-military co-operation]].
* The '''deputy assistant secretary of defense for defense continuity and mission assurance''' is responsible for the development of policies and plans for [[continuity of government]], [[mission assurance]], [[counterterrorism]], [[emergency management]], and [[critical infrastructure protection]].

=== Special operations and low-intensity conflict ===
The '''[[Assistant Secretary of Defense for Special Operations/Low Intensity Conflict & Interdependent Capabilities|assistant secretary of defense for special operations/low-intensity conflict]]''' (ASD(SO/LIC)) is responsible for the policy, resources, strategic capabilities and force transformation, and oversight of special operations and low-intensity conflict matters of the [[United States Department of Defense]] across [[counterterrorism]], [[unconventional warfare]], direct action, [[special reconnaissance]], [[foreign internal defense]], civil affairs, information and psychological operations, and [[counterproliferation]] of [[weapons of mass destruction]].
* The '''deputy assistant secretary of defense for counternarcotics and global threats''' is responsible for the policy, resources, strategic capabilities and force transformation, and oversight of special capabilities for counternarcotics and global threats.
* The '''deputy assistant secretary of defense for stability and humanitarian affairs''' is responsible for the policy, resources, strategic capabilities and force transformation, and oversight of conflict stabilization activities, peace operations, and humanitarian relief efforts.
* The '''deputy assistant secretary of defense for special operations and combatting terrorism''' is responsible for the policy, resources, strategic capabilities and force transformation, and oversight of [[counterterrorism]], [[counterinsurgency]], [[foreign internal defense]], and [[psychological operations]] as well as providing staff oversight of the [[United States Special Operations Command]] resources, budget, and program development issues.

=== Indo-Pacific security affairs ===
The '''[[Assistant Secretary of Defense for Indo-Pacific Security Affairs|assistant secretary of defense for Indo-Pacific security affairs]]''' (ASD(IPSA)) is responsible for international security strategy, defense policy, and oversight of security cooperation programs relating to the [[Indo-Pacific]] region.
* The '''deputy assistant secretary of defense for East Asia''' provides advice on international security strategy, defense policy, and oversight of security cooperation programs relating to [[Taiwan]], [[Mongolia]], [[Japan]], [[South Korea]], and [[North Korea]].
* The '''deputy assistant secretary of defense for China''' provides advice on international security strategy, defense policy, and bilateral security relations relating to [[China]] (Including [[Hong Kong]]).
* The '''deputy assistant secretary of defense for South and Southeast Asia''' provides advice on international security strategy, defense policy, and oversight of security cooperation programs relating to [[India]], [[Bangladesh]], [[Bhutan]], [[Diego Garcia]] (in conjunction with ASD(ISA)), [[Maldives]], [[Nepal]], [[Sri Lanka]], [[Brunei]], [[Burma]], [[Cambodia]], [[East Timor]], [[Indonesia]], [[Laos]], [[Malaysia]], [[Philippines]], [[Singapore]], [[Thailand]], [[Vietnam]], [[Australia]], [[New Zealand]], [[Papua New Guinea]], and the [[Pacific Islands]] nations.
* The '''deputy assistant secretary of defense for Afghanistan, Pakistan, and Central Asia''' provides advice on international security strategy, defense policy, and oversight of security cooperation programs relating to [[Afghanistan]], [[Pakistan]], [[Kazakhstan]], [[Kyrgyzstan]], [[Tajikistan]], [[Turkmenistan]], and [[Uzbekistan]].

=== Space policy ===
The '''[[assistant secretary of defense for space policy]]''' (ASD(SP)) is responsible for the overall supervision of DoD policy for space warfighting, encompassing the Department’s strategic capabilities for integrated deterrence: space, nuclear weapons, cyber, missile defense, electromagnetic warfare, and countering weapons of mass destruction. Additionally, this position served as the Principal Cyber Advisor to the Secretary of Defense.
* The '''deputy assistant secretary of defense for nuclear and cwmd policy''' provides advice on developing strategies, informing policies, and conducting oversight of nuclear deterrence policy and arms control, as well as developing and overseeing the implementation of strategies and policies of all countering weapons of mass destruction policy issues.
* The '''deputy assistant secretary of defense for cyber policy''' provides advice on establishing DoD cyberspace policy and strategy, providing guidance and oversight on DoD cyberspace activities, and managing DoD’s primary external relationships across the U.S. government, key domestic stakeholders, and our allies and partners.
* The '''deputy assistant secretary of defense for space and missile defense''' provides advice on space and integrated air and missile defense posture and policies.
* The '''deputy principal cyber advisor''' provides advice on military cyber forces and activities and the implementation of the cyber strategy and execution of the cyber posture review.

=== Defense POW/MIA Accounting Agency ===
The '''director of the [[Defense POW/MIA Accounting Agency]]''' is responsible for the [[personnel recovery]] of United States Department of Defense personnel who are listed as [[Prisoners of War|prisoners of war]] (POW) or [[Missing In Action|missing in action]] (MIA), from all past wars and conflicts around the world.

=== Defense Security Cooperation Agency ===
The '''director of the [[Defense Security Cooperation Agency]]''' is responsible for providing allies and partner nations with financial and technical assistance, transfer of defense matériel, training, and the promotion of military-to-military contacts.

=== Defense Technology Security Administration ===
The '''director of the [[Defense Technology Security Administration]]''' is responsible for the formulation and enforcement of technology security policies related to international transfers of defense-related goods, services, and technologies.

==Budget==
{{update-section|date=November 2017}}

===Budget features===
*'''Defense Critical Infrastructure Program (DCIP)''': Oversees policy formulation and strategic planning for the Defense Critical Infrastructure Program, to include the Defense Industrial Base, which provides defense-related products and services that are essential to equip; mobilize; deploy and sustain military operations, enabling the Warfighter to minimize risk. Ensures the resiliency of networked infrastructure assets, whether owned or operated by the DoD or private industry, that are critical to executing military missions. Activities include the identification, assessment, monitoring, and risk management of cyber and physical infrastructure assets critical to the execution of the National Military Strategy. DCIP is run under the auspices of the [[Assistant Secretary of Defense for Homeland Defense and Americas' Security Affairs|Office of the Assistant Secretary of Defense for Homeland Defense and Americas' Security Affairs]], where it is overseen by the DASD, Homeland Defense Strategy and Force Planning.
*'''Global Threat Management''': Provides policy, guidance and oversight on existential threats, supranational threats and [[non-state actor]] threats. OUSD(P) fulfills this global mission by crafting and implementing initiatives to expand cultural understanding throughout the world in governed and ungoverned areas to aid in preventing the expansion of terrorist cells. Utilizes table top exercises to enable Members of Congress, Administration Officials, and DoD personnel to form strategies in addressing catastrophic security events. Active research and involvement in the ever-changing cyber environment to protect security assets and prevent sophisticated threats in cyberspace from adversaries domestic and foreign. This funding appears to primarily support the programs of the [[Assistant Secretary of Defense for Global Strategic Affairs|Office of the Assistant Secretary of Defense for Global Strategic Affairs]].
*'''Homeland Defense Support Activities''': Formulates policy and conducts DoD strategic planning for homeland defense and defense support of civil authorities, including installation preparedness; CBRNE preparedness and consequence management; border security and National Security Special Events. Supports the U.S. Northern Command in homeland defense strategy, and enhances the U.S. Southern Command mission through engagement with the ministries of defense of Western Hemisphere nations. It supervises intradepartmental and inter-agency coordination of the above issues. Conducts oversight of DoD processes to exercise force readiness through the National Exercise Program. Manages defense continuity and conducts crisis management. This funding appears to primarily support the programs of the [[Assistant Secretary of Defense for Homeland Defense and Americas' Security Affairs|Office of the Assistant Secretary of Defense for Homeland Defense and Americas' Security Affairs]].
*'''Policy Planning and Integration''': OUSD(P) coordinates activities to aid in formulating strategies for DoD programs at national and international levels. This involves establishing and monitoring strategic direction, planning and force development as laid out in reporting documents such as the Quadrennial Defense Review (QDR) and Defense Planning and Programming Guidance (DPPG). OUSD(P) ensures decisions are not made in a vacuum by integrating policies and resources related to humanitarian efforts and their compliance with international laws. Initiates crisis decision-making in an interagency setting; creates forums to explore emerging national security issues; and examines the capabilities and limitations of national power through various instruments. Funding allows interagency integration and coordination to determine requirements for potential dual-use application of Defense assets.
*'''Regional Security Affairs''': Provides analysis of management of cultural situations in nation states and oversight to military joint ventures and cooperative DoD-Foreign government programs including educational, training, and developmental opportunities. Using a variety of resources, maintains regional expertise to support DoD leadership in forming and implementing strategies and contributes to coordinating holistic government engagement in programs and policies. Regional expertise provides the ability to: monitor and solve security cooperation issues, effectively execute coalition management, monitor international security operations, and further develop cooperative relations with foreign countries. This funding appears to primarily support the programs of the [[Assistant Secretary of Defense for Asian and Pacific Security Affairs|Office of the Assistant Secretary of Defense for Asian and Pacific Security Affairs]] and [[Assistant Secretary of Defense for International Security Affairs|Office of the Assistant Secretary of Defense for International Security Affairs]]
*'''Rewards Program''': Provides funds to publicize the program and pay rewards for information to disrupt international terrorist activities.
*'''Travel''': This funding supports travel in support of the OUSD(P) mission.
*'''US Mission to NATO''': Funding provides regional stability interface with US allies, NATO resolution of regional conflicts, response to terrorism and unstable conditions in fragile and failed nation states that include NATO involvement, weapons of mass destruction bilateral measures, and support of overseas facilities.
*'''Warfighting Support Activities''': OUSD(P) provides resources to orchestrate the development of special technologies and capabilities. It sustains these efforts by conducting in-depth analyses of the assignment of additional military and civilian personnel to long-term, non-intelligence positions in high-priority countries. Prepares the military for confronting threats in culturally diverse countries, supports policies and strategies that develop skills unique to counterinsurgency and stabilization efforts; reinforces and builds international support over shared security concerns, [[homeland security]], counterterrorism and other critical nation alliances, and promotes humanitarian activities through military resources in a non-combative manner. Provides funds to pay rewards for information to disrupt international terrorist activities and enhance US security capabilities. This funding appears to primarily support the programs of the [[Assistant Secretary of Defense for Special Operations/Low Intensity Conflict & Interdependent Capabilities|Office of the Assistant Secretary of Defense for Special Operations/Low Intensity Conflict & Interdependent Capabilities]]

== List of under secretaries of defense for policy==
{| class="wikitable" style="text-align:center;"
|-
! scope="col" | {{abbr|No.|Number}}
! scope="col" | Portrait
! scope="col" | Under Secretary<ref name="history">{{cite web |url=https://history.defense.gov/Portals/70/Documents/key_officials/KeyOfficials-2024-03-18.pdf?ver=OAdUrz6zMkTKcC9HKlI9nQ%3d%3d |title=Department of Defense Key Officials |publisher=Historical Office, OSD |year=2024 |access-date=5 April 2024}}</ref>
! scope="col" | Took office
! scope="col" | Left office
! scope="col" | Time in office
! scope="col" | [[United States Secretary of Defense|Secretary of Defense]]
! scope="col" | [[President of the United States|President]]
! scope="col" | {{abbr|Ref(s)|Reference(s)}}
|-
{{Officeholder table
| order             = 1
| image             = Stanley Rogers Resor, official photo.jpg
| officeholder      = [[Stanley Rogers Resor]]
| born_year         = 
| died_year         = 
| term_start        = 14 August 1978
| term_end          = 1 April 1979
| timeinoffice      = {{ayd|14 August 1978|1 April 1979}}
| alt_officeholder  = [[Harold Brown (Secretary of Defense)|Harold Brown]]
| alt_officeholder2 = 
| coalition         = [[Jimmy Carter]]
| ref               = -
}}
{{Officeholder table
| order             = 2
| image             = Robert Komer.jpg
| officeholder      = [[Robert Komer]]
| born_year         = 
| died_year         = 
| term_start        = 24 October 1979
| term_end          = 20 January 1981
| timeinoffice      = {{ayd|24 October 1979|20 January 1981}}
| alt_officeholder  = [[Harold Brown (Secretary of Defense)|Harold Brown]]
| alt_officeholder2 = 
| coalition         = [[Jimmy Carter]]
| ref               = -
}}
{{Officeholder table
| order             = 3
| image             = Portrait of Dr. Fred C. Ikle, Under Secretary of Defense for Policy.jpg
| officeholder      = [[Fred Iklé]]
| born_year         = 
| died_year         = 
| term_start        = 2 April 1981
| term_end          = 19 February 1988
| timeinoffice      = {{ayd|2 April 1981|19 February 1988}}
| alt_officeholder  = [[Caspar Weinberger]]
| alt_officeholder2 = [[Frank Carlucci]]
| coalition         = [[Ronald Reagan]]
| ref               = -
}}
{{Officeholder table
| order             = 4
| image             = Paul Wolfowitz.jpg
| officeholder      = [[Paul Wolfowitz]]
| born_year         = 
| died_year         = 
| term_start        = 15 May 1989
| term_end          = 19 January 1993
| timeinoffice      = {{ayd|15 May 1989|19 January 1993}}
| alt_officeholder  = [[Dick Cheney]]
| alt_officeholder2 = 
| coalition         = [[George H. W. Bush]]
| ref               = -
}}
{{Officeholder table
| order             = 5
| image             = Frank G. Wisner as Ambassador.png
| officeholder      = [[Frank G. Wisner]]
| born_year         = 
| died_year         = 
| term_start        = 6 July 1993
| term_end          = 9 June 1994
| timeinoffice      = {{ayd|6 July 1993|9 June 1994}}
| alt_officeholder  = [[Les Aspin]]
| alt_officeholder2 = [[William J. Perry|William Perry]]
| coalition         = [[Bill Clinton]]
| ref               = -
}}
{{Officeholder table
| order             = 6
| image             = Portrait of Walter B. Slocombe, Under Secretary of Defense for Policy.jpg
| officeholder      = [[Walter B. Slocombe]]
| born_year         = 
| died_year         = 
| term_start        = 15 September 1994
| term_end          = 19 January 2001
| timeinoffice      = {{ayd|15 September 1994|19 January 2001}}
| alt_officeholder  = [[William J. Perry|William Perry]]
| alt_officeholder2 = [[William Cohen]]
| coalition         = [[Bill Clinton]]
| ref               = -
}}
{{Officeholder table
| order             = -
| image             = Defense.gov News Photo 980928-A-3569D-001.jpg
| officeholder      = [[Peter F. Verga]]
| born_year         = 
| died_year         = 
| term_start        = 20 January 2001
| term_end          = 16 July 2001
| timeinoffice      = {{ayd|20 January 2001|16 July 2001}}
| alt_officeholder  = [[Donald Rumsfeld]]
| alt_officeholder2 = 
| coalition         = [[George W. Bush]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = 7
| image             = Douglas J. Feith, 2001.jpg
| officeholder      = [[Douglas J. Feith]]
| born_year         = 
| died_year         = 
| term_start        = 16 July 2001
| term_end          = 8 August 2005
| timeinoffice      = {{ayd|16 July 2001|8 August 2005}}
| alt_officeholder  = [[Donald Rumsfeld]]
| alt_officeholder2 = 
| coalition         = [[George W. Bush]]
| ref               = -
}}
{{Officeholder table
| order             = 8
| image             = Eric S. Edelman 050805-A-0607L-001.jpg
| officeholder      = [[Eric S. Edelman]]
| born_year         = 
| died_year         = 
| term_start        = 9 February 2006
| term_end          = 20 January 2009
| timeinoffice      = {{ayd|9 February 2006|20 January 2009}}
| alt_officeholder  = [[Donald Rumsfeld]]
| alt_officeholder2 = [[Robert Gates]]
| coalition         = [[George W. Bush]]
| ref               = -
}}
{{Officeholder table
| order             = 9
| image             = Michele Flournoy official portrait.jpg
| officeholder      = [[Michèle Flournoy]]
| born_year         = 
| died_year         = 
| term_start        = 9 February 2009
| term_end          = 3 February 2012
| timeinoffice      = {{ayd|9 February 2009|3 February 2012}}
| alt_officeholder  = [[Robert Gates]]
| alt_officeholder2 = [[Leon Panetta]]
| coalition         = [[Barack Obama]]
| ref               = <ref name="multiple">{{cite news |first=Sara |last=Moore |title=Defense Policy Nominee Pledges Work on Iraq, Afghanistan, National Security |url=http://www.defenselink.mil/news/newsarticle.aspx?id=52720 |work=[[American Forces Press Service]] |date=16 January 2009 |access-date=21 January 2009 }}</ref>
}}
{{Officeholder table
| order             = 9
| image             = Defense.gov News Photo 090410-A-6816H-003.jpg
| officeholder      = [[James N. Miller]]
| born_year         = 
| died_year         = 
| term_start        = 18 February 2012
| term_end          = 8 January 2014
| timeinoffice      = {{ayd|18 February 2012|8 January 2014}}
| alt_officeholder  = [[Leon Panetta]]
| alt_officeholder2 = [[Chuck Hagel]]
| coalition         = [[Barack Obama]]
| ref               = -
}}
{{Officeholder table
| order             = -
| image             = Lumpkin Michael.jpg
| officeholder      = [[Michael D. Lumpkin]]
| born_year         = 
| died_year         = 
| term_start        = 9 January 2014
| term_end          = 23 June 2014
| timeinoffice      = {{ayd|9 January 2014|23 June 2014}}
| alt_officeholder  = [[Chuck Hagel]]
| alt_officeholder2 = 
| coalition         = [[Barack Obama]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = 10
| image             = Christine Wormuth USDP.jpg
| officeholder      = [[Christine Wormuth]]
| born_year         = 
| died_year         = 
| term_start        = 23 June 2014
| term_end          = 10 June 2016
| timeinoffice      = {{ayd|23 June 2014|10 June 2016}}
| alt_officeholder  = [[Chuck Hagel]]
| alt_officeholder2 = [[Ash Carter]]
| coalition         = [[Barack Obama]]
| ref               = -
}}
{{Officeholder table
| order             = -
| image             = Acting Under Secretary of Defense for Policy.jpg
| officeholder      = [[Brian P. McKeon]]
| born_year         = 
| died_year         = 
| term_start        = 10 June 2016
| term_end          = 20 January 2017
| timeinoffice      = {{ayd|10 June 2016|20 January 2017}}
| alt_officeholder  = [[Ash Carter]]
| alt_officeholder2 = 
| coalition         = [[Barack Obama]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Theresa_Whelan_Performing_Duties_of_USDP.jpg
| officeholder      = [[Theresa Whelan]]
| born_year         = 
| died_year         = 
| term_start        = 20 January 2017
| term_end          = 7 June 2017
| timeinoffice      = {{ayd|20 January 2017|7 June 2017}}
| alt_officeholder  = [[James Mattis]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = <ref>{{cite web|url=https://www.defense.gov/About/Biographies/Article/760188/theresa-whelan/|title=Theresa Whelan > U.S. DEPARTMENT OF DEFENSE > Biography View|website=www.defense.gov|access-date=20 April 2018}}</ref>
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Robert S. Karem.jpg
| officeholder      = [[Robert Karem]]
| born_year         = 
| died_year         = 
| term_start        = 7 June 2017
| term_end          = 27 October 2017
| timeinoffice      = {{ayd|7 June 2017|27 October 2017}}
| alt_officeholder  = [[James Mattis]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = David J. Trachtenberg.jpg
| officeholder      = [[David Trachtenberg]]
| born_year         = 
| died_year         = 
| term_start        = 27 October 2017
| term_end          = 8 January 2018
| timeinoffice      = {{ayd|27 October 2017|8 January 2018}}
| alt_officeholder  = [[James Mattis]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = 11
| image             = John Rood official photo.jpg
| officeholder      = [[John Rood]]
| born_year         = 
| died_year         = 
| term_start        = 9 January 2018
| term_end          = 28 February 2020
| timeinoffice      = {{ayd|9 January 2018|28 February 2020}}
| alt_officeholder  = [[James Mattis]]
| alt_officeholder2 = [[Mark Esper]]
| coalition         = [[Donald Trump]]
| ref               = -
}}
{{Officeholder table
| order             = -
| image             = James H. Anderson official photo.jpg
| officeholder      = [[James Anderson (Defense official)|James Anderson]]
| born_year         = 
| died_year         = 
| term_start        = 1 March 2020
| term_end          = 10 November 2020
| timeinoffice      = {{ayd|1 March 2020|10 November 2020}}
| alt_officeholder  = [[Mark Esper]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = <ref>{{Cite web|last1=Seligman|first1=Lara|last2=Lippman|first2=Daniel|date=10 November 2020|title=Pentagon's top policy official resigns after clashing with the White House|url=https://www.politico.com/news/2020/11/10/pentagon-top-policy-official-resigns-435693|access-date=10 November 2020|website=[[POLITICO]]|language=en}}</ref>
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Anthony J. Tata official photo.jpg
| officeholder      = [[Anthony Tata]]
| born_year         = 
| died_year         = 
| term_start        = 10 November 2020
| term_end          = 20 January 2021
| timeinoffice      = {{ayd|10 November 2020|20 January 2021}}
| alt_officeholder  = [[Christopher C. Miller]] (acting)
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = <ref>{{Cite news |last1=Seligman |first1=Lara |last2=Lippman |first2=Daniel |date=November 10, 2020 |title=Official who once called Obama a 'terrorist leader' takes over Pentagon policy |language=en |work=Politico |url=https://www.politico.com/news/2020/11/10/pentagon-top-policy-official-resigns-435693 |access-date=November 10, 2020}}</ref>
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Thomas M. Williams.jpg
| officeholder      = [[Thomas M. Williams|Thomas Williams]]
| born_year         = 
| died_year         = 
| term_start        = 15 January 2021
| term_end          = 20 January 2021
| timeinoffice      = {{ayd|15 January 2021|20 January 2021}}
| alt_officeholder  = [[Christopher C. Miller]] (acting)
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = <ref>[https://www.defense.gov/About/Biographies/Biography/Article/2272931/thomas-m-williams/ defense.gov]</ref>
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Amanda J. Dory.jpg
| officeholder      = [[Amanda J. Dory]]
| born_year         = 
| died_year         = 
| term_start        = 20 January 2021
| term_end          = 28 April 2021
| timeinoffice      = {{ayd|20 January 2021|28 April 2021}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = 12
| image             = Dr. Colin H. Kahl.jpg
| officeholder      = [[Colin Kahl]]
| born_year         = 
| died_year         = 
| term_start        = 28 April 2021
| term_end          = 17 July 2023
| timeinoffice      = {{ayd|28 April 2021|17 July 2023}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
}}
{{Officeholder table
| order             = -
| image             = Sasha N. Baker (2).jpg
| officeholder      = [[Sasha Baker]]
| born_year         = 
| died_year         = 
| term_start        = 18 July 2023
| term_end          = 26 April 2024
| timeinoffice      = {{ayd|18 July 2023|26 April 2024}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Amanda J. Dory.jpg
| officeholder      = [[Amanda J. Dory]]
| born_year         = 
| died_year         = 
| term_start        = 27 April 2024
| term_end          = 22 January 2025
| timeinoffice      = {{ayd|27 April 2024|22 January 2025}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Alexander Velez-Green (2).jpg
| officeholder      = [[Alexander Velez-Green]]
| born_year         = 
| died_year         = 
| term_start        = 22 January 2025
| term_end          = 15 April 2025
| timeinoffice      = {{ayd|22 January 2025|15 April 2025}}
| alt_officeholder  = [[Pete Hegseth]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = 13
| image             = Elbridge A. Colby (2).jpg
| officeholder      = [[Elbridge Colby]]
| born_year         = 
| died_year         = 
| term_start        = 15 April 2025
| timeinoffice      = {{ayd|15 April 2025}}
| alt_officeholder  = [[Pete Hegseth]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
| acting            = no
}}
|}

==Principal Deputy==
The '''Principal Deputy Under Secretary of Defense for Policy''' is the chief staff assistant to the USD(P). Originally established as the ''Deputy Under Secretary of Defense (Policy)'' by the National Defense Authorization Act for FY 1992–93 (P.L. 102–190), the post was re-designated ''Principal Deputy Under Secretary of Defense (Policy)'', or PDUSD(P) in December 1999 by DoD Directive 5111.3.<ref name="multiple"/> The PDUSD(P) provides advice and assistance to the Secretary of Defense, Deputy Secretary of Defense, and USD(P) on national security policy, military strategy, and defense policy.
{| class="wikitable" style="text-align:center;"
|-
! scope="col" | {{abbr|No.|Number}}
! scope="col" | Portrait
! scope="col" | Deputy Under Secretary<ref name="history">{{cite web |url=https://history.defense.gov/Portals/70/Documents/key_officials/KeyOfficials-2024-03-18.pdf?ver=OAdUrz6zMkTKcC9HKlI9nQ%3d%3d |title=Department of Defense Key Officials |publisher=Historical Office, OSD |year=2024 |access-date=5 April 2024}}</ref>
! scope="col" | Took office
! scope="col" | Left office
! scope="col" | Time in office
! scope="col" | [[United States Secretary of Defense|Secretary of Defense]]
! scope="col" | [[President of the United States|President]]
! scope="col" | {{abbr|Ref(s)|Reference(s)}}
|-
{{Officeholder table
| order             = 1
| image             = Scooter Libby.jpg
| officeholder      = [[Scooter Libby|I. Lewis Libby]]
| born_year         = 
| died_year         = 
| term_start        = 12 August 1992
| term_end          = 10 January 1993
| timeinoffice      = {{ayd|12 August 1992|10 January 1993}}
| alt_officeholder  = [[Paul Wolfowitz]]
| alt_officeholder2 = [[Dick Cheney]]
| coalition         = [[George H. W. Bush]]
| ref               = -
}}
{{Officeholder table
| order             = 2
| image             = Portrait of Walter B. Slocombe, Under Secretary of Defense for Policy.jpg
| officeholder      = [[Walter B. Slocombe]]
| born_year         = 
| died_year         = 
| term_start        = 1 June 1993
| term_end          = 14 September 1994
| timeinoffice      = {{ayd|1 June 1993|14 September 1994}}
| alt_officeholder  = [[Les Aspin]]
| alt_officeholder3 = [[William J. Perry]]
| coalition         = [[Bill Clinton]]
| ref               = -
}}
{{Officeholder table
| order             = 3
| image             = Defense.gov News Photo 940908-A-3569D-001.jpg
| officeholder      = [[Jan M. Lodal]]
| born_year         = 
| died_year         = 
| term_start        = 3 October 1994
| term_end          = 30 September 1998
| timeinoffice      = {{ayd|3 October 1994|30 September 1998}}
| alt_officeholder  = [[William J. Perry]]
| alt_officeholder2 = [[William S. Cohen]]
| coalition         = [[Bill Clinton]]
| ref               = -
}}
{{Officeholder table
| order             = 4
| image             = Defense.gov News Photo 981106-A-3569D-001.jpg
| officeholder      = [[James M. Bodner]]
| born_year         = 
| died_year         = 
| term_start        = 1 October 1998
| term_end          = 19 January 2001
| timeinoffice      = {{ayd|1 October 1998|19 January 2001}}
| alt_officeholder  = [[William S. Cohen]]
| alt_officeholder2 = 
| coalition         = [[Bill Clinton]]
| ref               = -
}}
{{Officeholder table
| order             = 5
| image             = Stephen Cambone, official DoD photo portrait, 2003.jpg
| officeholder      = [[Stephen Cambone|Stephen A. Cambone]]
| born_year         = 
| died_year         = 
| term_start        = 25 July 2001
| term_end          = 1 July 2002
| timeinoffice      = {{ayd|25 July 2001|1 July 2002}}
| alt_officeholder  = [[Donald H. Rumsfeld]]
| alt_officeholder2 = 
| coalition         = [[George W. Bush]]
| ref               = -
}}
{{Officeholder table
| order             = 5
| image             = Defense.gov News Photo 030326-A-3569D-001.jpg
| officeholder      = [[Christopher Ryan Henry]]
| born_year         = 
| died_year         = 
| term_start        = 7 February 2003
| term_end          = August 2008
| timeinoffice      = ~{{ayd|7 February 2003|15 August 2008}}
| alt_officeholder  = [[Donald H. Rumsfeld]]
| alt_officeholder2 = [[Robert M. Gates]]
| coalition         = [[George W. Bush]]
| ref               = -
}}
{{Officeholder table
| order             = -
| image             = Defense.gov News Photo 980928-A-3569D-001.jpg
| officeholder      = [[Peter F. Verga]]
| born_year         = 
| died_year         = 
| term_start        = August 2008
| term_end          = 1 April 2009
| timeinoffice      = ~{{ayd|15 August 2008|1 April 2009}}
| alt_officeholder  = [[Robert M. Gates]]
| alt_officeholder2 = 
| coalition         = [[George W. Bush]]
| coalition2        = [[Barack Obama]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = 6
| image             = Defense.gov News Photo 090410-A-6816H-003.jpg
| officeholder      = [[James N. Miller]]
| born_year         = 
| died_year         = 
| term_start        = 2 April 2009
| term_end          = 24 May 2012
| timeinoffice      = {{ayd|2 April 2009|24 May 2012}}
| alt_officeholder  = [[Robert M. Gates]]
| alt_officeholder2 = 
| coalition         = [[Barack Obama]]
| ref               = -
}}
{{Officeholder table
| order             = 7
| image             = Kathleen Hicks.jpg
| officeholder      = [[Kathleen Hicks]]
| born_year         = 
| died_year         = 
| term_start        = 24 May 2012
| term_end          = 2 July 2013
| timeinoffice      = {{ayd|24 May 2012|2 July 2013}}
| alt_officeholder  = [[Chuck Hagel]]
| alt_officeholder2 = 
| coalition         = [[Barack Obama]]
| ref               = -
}}
{{Officeholder table
| order             = 8
| image             = Acting Under Secretary of Defense for Policy.jpg
| officeholder      = [[Brian P. McKeon]]
| born_year         = 
| died_year         = 
| term_start        = 28 July 2014
| term_end          = 10 June 2016
| timeinoffice      = {{ayd|28 July 2014|10 June 2016}}
| alt_officeholder  = [[Ash Carter]]
| alt_officeholder2 = 
| coalition         = [[Barack Obama]]
| ref               = -
}}
{{Officeholder table
| order             = -
| image             = David Shear 2015.jpg
| officeholder      = [[David B. Shear]]
| born_year         = 
| died_year         = 
| term_start        = 10 June 2016
| term_end          = 20 January 2017
| timeinoffice      = {{ayd|10 June 2016|20 January 2017}}
| alt_officeholder  = [[Ash Carter]]
| alt_officeholder2 = 
| coalition         = [[Barack Obama]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = 9
| image             = David J. Trachtenberg.jpg
| officeholder      = [[David Trachtenberg]]
| born_year         = 
| died_year         = 
| term_start        = 27 October 2017
| term_end          = 19 July 2019
| timeinoffice      = {{ayd|27 October 2017|19 July 2019}}
| alt_officeholder  = [[James Mattis]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
}}
{{Officeholder table
| order             = -
| image             = James H. Anderson official photo.jpg
| officeholder      = [[James Anderson (Defense official)|James Anderson]]
| born_year         = 
| died_year         = 
| term_start        = 23 July 2019
| term_end          = 24 April 2020
| timeinoffice      = {{ayd|23 July 2019|24 April 2020}}
| alt_officeholder  = [[Mark Esper]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Daniel R. Green.jpg
| officeholder      = [[Daniel R. Green]]
| born_year         = 
| died_year         = 
| term_start        = 24 April 2020
| term_end          = 8 June 2020
| timeinoffice      = {{ayd|24 April 2020|8 June 2020}}
| alt_officeholder  = [[Mark Esper]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = 10
| image             = James H. Anderson official photo.jpg
| officeholder      = [[James Anderson (Defense official)|James Anderson]]
| born_year         = 
| died_year         = 
| term_start        = 8 June 2020
| term_end          = 10 November 2020
| timeinoffice      = {{ayd|8 June 2020|10 November 2020}}
| alt_officeholder  = [[Mark Esper]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
| acting            =
}}
{{Officeholder table
| order             = -
| image             = Thomas M. Williams.jpg
| officeholder      = [[Thomas M. Williams]]
| born_year         = 
| died_year         = 
| term_start        = 10 November 2020
| term_end          = 20 January 2021
| timeinoffice      = {{ayd|10 November 2020|20 January 2021}}
| alt_officeholder  = [[Christopher C. Miller]] (acting)
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Jennifer C. Walsh.jpg
| officeholder      = [[Jennifer C. Walsh]]
| born_year         = 
| died_year         = 
| term_start        = 20 January 2021
| term_end          = 28 April 2021
| timeinoffice      = {{ayd|20 January 2021|28 April 2021}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Amanda J. Dory.jpg
| officeholder      = [[Amanda J. Dory]]
| born_year         = 
| died_year         = 
| term_start        = 29 April 2021
| term_end          = 23 August 2021
| timeinoffice      = {{ayd|29 April 2021|23 August 2021}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Mara E. Karlin (3).jpg
| officeholder      = [[Mara Karlin]]
| born_year         = 
| died_year         = 
| term_start        = 23 August 2021
| term_end          = 14 February 2022
| timeinoffice      = {{ayd|23 August 2021|14 February 2022}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = 11
| image             = Sasha N. Baker (2).jpg
| officeholder      = [[Sasha Baker]]
| born_year         = 
| died_year         = 
| term_start        = 14 February 2022
| term_end          = 26 April 2024
| timeinoffice      = {{ayd|14 February 2022|26 April 2024}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
}}
{{Officeholder table
| order             = -
| image             = Mara E. Karlin (3).jpg
| officeholder      = [[Mara Karlin]]
| born_year         = 
| died_year         = 
| term_start        = 4 January 2023
| term_end          = 24 April 2023
| timeinoffice      = {{ayd|23 August 2021|14 February 2022}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Mara E. Karlin (3).jpg
| officeholder      = [[Mara Karlin]]
| born_year         = 
| died_year         = 
| term_start        = 18 July 2023
| term_end          = 20 December 2023
| timeinoffice      = {{ayd|23 August 2021|14 February 2022}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Melissa G. Dalton (2).jpg
| officeholder      = [[Melissa Dalton]]
| born_year         = 
| died_year         = 
| term_start        = 26 April 2024
| term_end          = 29 May 2024
| timeinoffice      = {{ayd|26 April 2024|29 May 2024}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Cara L. Abercrombie (2).jpg
| officeholder      = [[Cara L. Abercrombie]]
| born_year         = 
| died_year         = 
| term_start        = 29 May 2024
| term_end          = 20 January 2025
| timeinoffice      = {{ayd|29 May 2024|20 January 2025}}
| alt_officeholder  = [[Lloyd Austin]]
| alt_officeholder2 = 
| coalition         = [[Joe Biden]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Amanda J. Dory.jpg
| officeholder      = [[Amanda J. Dory]]
| born_year         = 
| died_year         = 
| term_start        = 22 January 2025
| term_end          = 17 March 2025
| timeinoffice      = {{ayd|22 January 2025|17 March 2025}}
| alt_officeholder  = [[Pete Hegseth]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
| acting            = y
}}
{{Officeholder table
| order             = -
| image             = Austin J. Dahmer.jpg
| officeholder      = [[Austin Dahmer]]
| born_year         = 
| died_year         = 
| term_start        = 17 March 2025
| timeinoffice      = {{ayd|17 March 2025}}
| alt_officeholder  = [[Pete Hegseth]]
| alt_officeholder2 = 
| coalition         = [[Donald Trump]]
| ref               = -
| acting            = y
}}
|}

== Notes and references ==
{{Reflist}}

{{Current US Department of Defense Secretaries}}
{{US Department of Defense Secretaries}}

[[Category:United States Under Secretaries of Defense for Policy| ]]