In 1943 Sievers became director of the Institut für Wehrwissenschaftliche Zweckforschung (Institute for Military Scientific Research), which conducted extensive experiments using human subjects. He also assisted in assembling a collection of skulls and skeletons for August Hirt's study at the Reichsuniversität Straßburg as a part of which 112 Jewish prisoners were selected and killed, after being photographed and their anthropological measurements taken.[2]