Most people can conjure up a particular set of images when they think of labor camps under the Third Reich; usually, they picture emaciated prisoners in striped uniforms, performing heavy manual labor and subject to frequent beatings from sadistic SS guards. There is an essential truth to those images, in that they accurately reflect the experiences of many thousands of people. At the same time, however, the term labor camp can be deceptive. On the one hand, the Germans classified a great many places of detention as forced labor camps (Zwangsarbeitslager), but the term tells us little about conditions, which often differed radically from camp to camp. On the other hand, forced labor was a central part of life in most camps and ghettos, with or without the label. In fact, by the last years of the war, forced labor was ubiquitous in Germany, and some knowledge of the system is essential to an understanding of the Third...