of South Vietnam. These forces included the 'liberation army' directed by the VC, which first became active in the late 1950s and the PAVN, the army of its northern sponsor. The nucleus of VC forces consisted of returning communist cadre from North Vietnam. In 1954 this cadre had evacuated to the north after the Geneva Accords ending the First Indochina War. Also involved were "stay behind" communist cadre, and others who wanted an armed revolution to overthrow the government of South Vietnamese (GSV). The VC were successful in recruiting local people into their ranks. Communications were maintained with the North, which sent it additional cadre, army personnel and equipment. ARVN J-2 (military intelligence) discovered "a steady rise in VC strength levels". The American advisors of MAAG Vietnam were familiar with ARVN J-2 records, but "this unfavorable trend had not appeared in MAAG reporting" because in 1960 it had "no intelligence shop". Initial CIA "efforts to fill this gap were constrained by the limited volume and reliability of Vietnamese police reporting [CIA's chief source] about VC activity and about local communist military and political order of battle". In 1965 American combat troops landed in South Vietnam; thereafter, MACV assumed the duties of MAAG Vietnam. The O/B numbers for the communist forces were kept, and work done for MACV's own compilation of the enemy's strength and composition, but apparently the VC O/B were not regularly updated using new reports from the field. In 1965 the CIA assigned an analyst, Sam Adams, to investigate VC motivation and morale. Changing rates of defections and desertion from the VC, and the numbers involved, led him to inquire about the overall VC O/B. He found that MACV was then estimating the strength of the VC, including its PAVN soldiers, at 280,000. CIA: VC O/B new numbers Adams, a CIA mid-level analyst, discovered what appeared to be a large gap between MACV O/B numbers and the actual count of VC in the field. Adams relied on multiple sources of information, including his own interviews with ARVN military officers, and GSV records on the conflict, especially files from its Chieu Hoi program which focused on defectors from the VC. Adams also used CIA data derived directly from American MACV and its J-2 (military intelligence), which contained translations of captured documents, of interrogations with enemy POWs, and intercepts, as well as photo-reconnaissance. Key to his research had been his