Headquarters, U.S. Marine Corps (HQMC), located in Arlington, Virginia, consists of the Commandant of the Marine Corps and those staff agencies that advise and assist him in discharging his responsibilities prescribed by law and higher authority. The Commandant is directly responsible to the Secretary of the Navy for the total performance of the Marine Corps. This includes the administration, discipline, internal organization, training requirements, efficiency, and readiness of the service. The function, composition, and general duties of HQMC are defined in the United States Code, Title 10, Subtitle C, Part 1, Chapter 506 (Headquarters, Marine Corps).
The United States Marine Corps (USMC) is a branch of the U.S. military responsible for providing power projection from the sea, utilizing the mobility of the U.S. Navy to rapidly deliver combined-arms task forces to global crises. Alongside the U.S. Navy, the Marine Corps operates under the United States Department of the Navy.
The Marine Corps, with authorized end strength of 202,100 active duty and 39,600 reserve Marines, is the smallest of the United States armed forces in the Department of Defense.