The defeat of South Vietnam was arguably America's worst foreign policy disaster of the 20th Century. Yet a complete understanding of the endgame, from the 27 January 1973 signing of the Paris Peace Accords to South Vietnam's surrender on 30 April 1975, has eluded us. This work addresses that deficit. It represents a culmination of exhaustive research in three distinct areas: primary source documents from American archives, North Vietnamese publications containing primary and secondary source material, and dozens of articles and numerous interviews with key South Vietnamese participants.