About

DOD Seal

The Department of Defense is America's largest government agency. With our military tracing its roots back to pre-Revolutionary times, the department has grown and evolved with our nation. Our mission is to provide the military forces needed to deter war and ensure our nation's security.

$740.5 Billion

National Defense Budget

2.91 Million

Service Members & Civilians

4,800 Sites

In Over 160 Countries

Armed Forces

The Army, Marine Corps, Navy, Air Force, Space Force and Coast Guard are the armed forces of the United States. The Army National Guard and the Air National Guard are reserve components of their services and operate in part under state authority.

Combatant Commands

The Defense Department has 11 combatant commands, each with a geographic or functional mission that provides command and control of military forces in peace and war.

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Leaders

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DOD Seal

Office of the Secretary of Defense

Top civilian defense decision-makers work with the secretary to develop policy, operational and fiscal plans, manage resources and evaluate programs.

Secretary Priorities

The Department of Defense is focused on the following areas:

Defend the Nation

Succeed Through Teamwork

Take Care of Our People

History

The Department of Defense is America's oldest and largest government agency, tracing its roots back to pre-Revolutionary times. Learn about DOD’s rich history and innovations.

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Headquarters

The Pentagon, with its iconic design, is the headquarters of the Department of Defense. Find out more about DOD’s mission and organization.

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Contact

FAQs

You have questions. We have answers. Search our most frequently asked questions.

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Press & Media

Covering the defense beat and the Pentagon? Here's what you need to know.

Media Queries