Recent interpretations of World War Two have stressed the decisive role of economics in the success of the Allies and especially in the failure of the Axis. Yet the place of labor in the war remains under-appreciated. ILWCH commissioned several essays for a special issue on wartime labor mobilization, forced and free. This introduction briefly compares Nazi Germany, Japan, the Soviet Union, and the United States, and highlights the implications of the differing wartime labor regimes for the postwar period.