The order of battle for the Viet Cong concerned a contested American intelligence issue of the Vietnam War. Arising In the mid-1960s, its focus was the count of enemy combatants. Often called the order of battle controversy, the debate came to divide the Central Intelligence Agency (CIA), and challenge military intelligence. The politics and strategy of the war became involved in the debate. Order of battle (O/B) is a military term for a description of the strength of an armed force, its composition and particulars. A key factor is the total number involved. Here the count was of communist forces in South Vietnam. While then chiefly the Viet Cong (VC), it also included forces coming from North Vietnam: the People's Army of Viet Nam (PAVN). This article addresses the order of battle (O/B) not for any single engagement of the war, but rather for the overall strength of communist forces in South Vietnam at the time, e.g., 1967. Determining the O/B number for VC and PAVN forces was complicated by the wide range of personnel involved, especially among VC. There were trained and equipped 'regular soldiers', but also other forces, e.g., rural militias, many part-time, with various or little training and weapons. In addition were politically organized support groups of civilians, some full-time, highly trained party cadres, often collectively called by American intelligence the Viet Cong Infrastructure (VCI). The American Military Assistance Command, Vietnam (MACV) was begun in 1962. MACV intelligence provided reports on the enemy O/B. A few years later the CIA, too, began to study the VC. A dispute then arose as to the number of enemy forces, because the CIA had arrived at significantly higher figures than MACV. During 1967 this controversy became widely known in American intelligence. It held important implications for how the Vietnam War was described to the American people, the prospects for victory. When the year's Special National Intelligence Estimate for Vietnam (SNIE 14-3-67) was prepared, it became difficult to reconcile the competing number estimates for VC. Charges were made, e.g., by Sam Adams an analyst for the CIA, that MACV's low numbers were the result of political interference with the data of intelligence work. Later that year the controversy was resolved in favor of the lower numbers which MACV had forcefully and persistently asserted. In January 1968, communist forces dramatically changed their low-profile strategy: they brazenly attacked many cities and other targets