Department of Defense Seal

The United States Department of Defense is the federal department charged with coordinating and supervising all agencies and functions of the government relating directly to national security and the military. The organization and functions of the DOD are set forth in Title 10 of the United States Code.

The DOD is the major tenant of The Pentagon building near Washington, D.C. and has three major components – the Department of the Army, the Department of the Navy, and the Department of the Air Force.