On September 21, 1961, the 5th SFG (A) was officially activated at Fort Bragg, North Carolina. Just one year later, elements of the 5th SFG (A) began serving temporary tours of duty in the Republic of South Vietnam, with the full deployment of the group by February 1965.

     One of the groups A Team's, A-502's mission was the defense of the 5th Special Forces Group Headquarters and the Nha Trang Air Installation. When it was determined that the defensive perimeter needed to include the greater Nha Trang City area, the responsibility for that assignment was given to Detachment A-502.

     From its operational base at Nha Trang, the group deployed throughout the four military regions within South Vietnam. The group's operational detachments established and manned camps at 270 locations throughout South Vietnam, training and leading indigenous forces of the Civilian Irregular Defense Groups. Additionally, Soldiers from the group led units of indigenous forces conducting reconnaissance, and direct-action missions throughout Southeast Asia.

     Team A-502 became the largest team in South Vietnam, and was given the responsibility for the internal security of this headquarters and the other buildings and compounds within the Na Trang area of operations. The team was at its greatest number in mid 1968 when it had approximately 56 men.