Becoming a close friend of Heydrich, Behrends was the first chief of the SD in Berlin.[5] He also served as Chief of Staff to Werner Lorenz in his capacity as head of the Hauptamt Volksdeutsche Mittelstelle (VOMI).[6] During the Second World War he was sent to Yugoslavia to lead the regional arm of the VOMI.[5] His star had fallen somewhat after Heydrich's death as Heinrich Himmler was unimpressed by him, sensing that he was too ambitious.[7]