“Normalization of relations” is a phrase of recent origin, widely used by scholars, politicians, and journalists. Defining normalization, however, is remarkably difficult. While we know a great deal about specific instances of normalization, we lack a sustained study of normalization itself, a gap this article begins to address. Using case studies of U.S. relations with China, Vietnam, and Cuba, this article examines the idea of normalization, its history, and its consequences. Focusing on pivotal moments in which “normalization” was at stake, we argue that in the American rendering, normalization was a process that unfolded in three phases. In turn, normalizing relations became a key nonmilitary means through which U.S. officials escalated and then deescalated the Cold War. Like other facets of U.S. diplomacy of the postwar period, normalization policies were premised on many of the assumptions and institutions of the “liberal international order” and have endured into the twenty-first century.