The Krulak–Mendenhall mission was a fact-finding expedition dispatched by the Kennedy administration to South Vietnam in early September 1963. The stated purpose of the expedition was to investigate the progress of the war by the South Vietnamese regime and its US military advisers against the Viet Cong insurgency. The mission was led by Victor Krulak and Joseph Mendenhall. Krulak was a major general in the United States Marine Corps, while Mendenhall was a senior Foreign Service Officer experienced in dealing with Vietnamese affairs.

Victor Harold Krulak was a decorated United States Marine Corps officer who saw action in World War II, Korea and Vietnam. Krulak, considered a visionary by fellow Marines, was the author of First to Fight: An Inside View of the U.S. Marine Corps and the father of the 31st Commandant of the Marine Corps, General Charles C. Krulak.