COSVN: Party secretary: Nguyễn Văn Linh (1961-64), Nguyễn Chí Thanh (1964-1967), Phạm Hùng (1967-1975). NLF: Nguyễn Hữu Thọ (chairman), Huỳnh Tấn Phát (general secretary, vice-chairman), Phung Van Cung (vice-chairman), Võ Chí Công (vice-chairman). PRG: Huỳnh Tấn Phát (president), Madame Nguyễn Thị Bình (foreign minister), Trần Nam Trung (minister of defense), Trương Như Tạng (minister of justice)

The Vietcong (Việt Cộng), or National Liberation Front, was a political organisation and army in South Vietnam and Cambodia that fought the United States and South Vietnamese governments during the Vietnam War (1959–1975). It had both guerrilla and regular army units, as well as a network of cadres who organized peasants in the territory it controlled. Many soldiers were recruited in South Vietnam, but others were attached to the People's Army of Vietnam (PAVN), the regular North Vietnamese army. During the war, communists and anti-war spokesmen insisted the Vietcong was an insurgency indigenous to the South, while the U.S. and South Vietnamese governments disputed this and portrayed the group as a tool of Hanoi. This allowed writers to distinguish northern communists from the southern communists, or Viet Cong. However, northerners and southerners were always under the same command structure. According to Hanoi's official history, the PLAF (Vietcong) was a branch of the PAVN.

Southern Vietnamese communists established the National Liberation Front in 1960 to encourage the participation of non-communists in the insurgency. Many of the Vietcong's core members were "regroupees," southern Vietminh who had resettled in the North after the Geneva Accord (1954). Hanoi gave the regroupees military training and sent them back to the South along the Ho Chi Minh trail in the early 1960s. The NLF called for Southerners to "overthrow the camouflaged colonial regime of the American imperialists" and to make "efforts toward the peaceful unification." The Vietcong's best-known action was the Tet Offensive, a massive assault on more than 100 South Vietnamese urban centers in 1968, including an attack on the US embassy in Saigon. The offensive riveted the attention of the world's media for weeks, but also overextended the Vietcong. Later communist offensives were conducted predominately by the PAVN. The group was dissolved in 1976 when North and South Vietnam were officially unified under a communist government.