Lieutenant General Tôn Thất Đính was an officer who served in the Army of the Republic of Vietnam (ARVN). He is best known as one of the key figures in the November 1963 coup that led to the arrest and assassination of Ngô Đình Diệm, the first president of the Republic of Vietnam, commonly known as South Vietnam.

In November 1963, President Ngô Đình Diệm and the Personalist Labor Revolutionary Party of the Republic of Vietnam were deposed by a group of CIA-backed Army of the Republic of Vietnam officers who disagreed with Diệm's handling of the Buddhist crisis and the North Vietnamese and Viet Cong threat to South Vietnam. In South Vietnam, the coup was referred to as Cách mạng 1-11-63.