The Vietnamese Rangers (Vietnamese: Biệt Động Quân), commonly known as the ARVN Rangers or Vietnamese Ranger Corp (VNRC), were the light infantry of the Army of the Republic of Vietnam. Trained and assisted by American Special Forces and Ranger advisers, the Vietnamese Rangers infiltrated beyond enemy lines in search and destroy missions. Initially trained as a counter-insurgency light infantry force by removing the fourth company each of the existing infantry battalions, they later expanded into a swing force capable of conventional as well as counter-insurgency operations, and were relied on to retake captured regions. Later during Vietnamization the Civilian Irregular Defense Group program was transferred from MACV and integrated as Border Battalions responsible for manning remote outposts in the Central Highlands.

Rangers were often regarded as among the most effective units in the war. Part of this was due to the specialized role of these units, given that they had their origins in French-raised Commando Units, the GCMA which were drawn from Viet Minh defectors and Tai-Kadai groups, operating in interdiction and counter-intelligence roles, and were trained specifically for counter-insurgency and rough-terrain warfare in the region. Ranger Units often had a US Military Adviser attached to these units although operated independently. With improvements in the ARVN from 1969 onward and the growing prestige of the Airborne and Marine Division, depredation had caused the Central Highlands-based Rangers to become manned by deserters, released convicts and Montagnards nevertheless the unit continued to operate in the Easter Offensive and frontier skirmishes in 1973 and 1974