Historians long have analyzed the emergence of the “final solution of the Jewish question” primarily on the basis of German documentation, devoting much less attention to wartime Jewish perceptions of the growing threat. Jürgen Matthäus fills this critical gap by showcasing the highly insightful reports compiled during the first half of World War II by two Geneva-based offices: those of Richard Lichtheim representing the Jewish Agency for Palestine and of Gerhart Riegner’s World Jewish Congress office. Since the first days of war, Lichtheim’s predictions of Jewish dead ran in the millions and increased progressively with the rising tide of Nazi rule over Europe. His and Riegner’s perceptions of German anti-Jewish policy resulted from shared goals and personal experiences as well as from their bureaus’ range of functions and the massive problems that impacted the gathering and communicating of information on the unfolding Holocaust in German-controlled Europe. Beyond the specifics of the wartime Geneva setting, these sources show how human cognition works in times of extreme crisis and contribute to a better understanding of the potential inherent in Jewish sources for gauging perpetrator actions. The reports and contextual information featured here reflect the first narratives on the Holocaust, their emergence, evolution, and importance for post-war historiography.