The war effort required that after 1942 many prisoner squads had to work far away from the camp. These crews, which were still the responsibility of Flossenbuerg, were scattered over Bavaria, Saxony, and the Czech Republic. A third of the more than 100 outlying work squads consisted of female prisoners, whose living and work conditions, in such places as Hersbruck and Leitmeritz, were often appalling. Here, after the Allies had bombed important arms factories, the military production was to be hidden in underground tunnels. The murderous tunnel construction caused the Flossenbuerg prisoners unimaginable suffering.

These prisoners, who were meant to be worked to death, were employed by organisations of the SS, of the army and of the Nazi party, as well as by arms factories, the German railway, police departments, city administrations, businesses deemed essential to the war effort and various individuals. Among the major arms firms who approached the SS for prison labour were Siemens, the Auto Union Co., Osram, Junkers and Messerschmitt. Since aside from being punished, the prisoners also performed the economic function of slave labour, in 1941 the concentration camps came under the direction of the Ministry of Economics ("WVHA").