Over the course of the long and violent twentieth century, only a minority of international crime perpetrators ever stood trial, and a central challenge of this era was the effort to ensure that not all these crimes remained unpunished. This required not only establishing a legal record but also courage, determination, and inventiveness in realizing justice. Defeating Impunity moves from the little-known trials of the 1920s to the Yugoslavia tribunal in the 2000s, from Belgium in 1914 to Ukraine in 1943, and to Stuttgart and D sseldorf in 1975. It illustrates the extent to which the language of law drew an international horizon of justice.