This monograph explores two major U.S. operations and the reaction to one enemy offensive to illustrate evidence of U.S. operational art in Vietnam. The operational level is identified as the corps headquarters responsible for nesting Military Assistance Command-Vietnam's (MACV) military guidance, the strategic direction issued by the Joint Chiefs of Staff, and the national government's aims with the tactical maneuver of subordinate divisions and battalions. During the Vietnam War, the Field Force served as the equivalent of the corps headquarters. The three case studies analyzed in this monograph are all drawn from II Field Force during the period 1967 to 1971. These case studies are Operation Cedar Falls and Operation Junction City (1967), the 1970 U.S. incursion into Cambodia under Operation Toan Thang, and II Field Force's reaction to the Tet offensive (1968). Through the analysis of these case studies, the question of operational art existing at the corps level during the Vietnam War is addressed, as is the identification of successful or unsuccessful leadership and staff practices in an asymmetric conflict.