The Gerstein Report was written in 1945 by Kurt Gerstein, Obersturmführer of the Waffen-SS, who served as Head of Technical Disinfection Services of the SS in World War II, and in that capacity supplied the hydrogen cyanide-based pesticide Zyklon B from Degesch (Deutsche Gesellschaft für Schädlingsbekämpfung) to Rudolf Höss in Auschwitz, and conducted the negotiations with the owners.[1] On 18 August 1942, along with Rolf Günther and Wilhelm Pfannenstiel, Gerstein witnessed the gassing of some 3,000 Jews in the extermination camp of Belzec in occupied Poland. The report features his eyewitness testimony.