Sicherheitsdienst

Sicherheitsdienst , full title Sicherheitsdienst des Reichsführers-SS , or SD, was the intelligence agency of the SS and the Nazi Party in Nazi Germany. Originating in 1931, the organization was the first Nazi intelligence organization to be established and was considered a sister organization with the Gestapo through integration of SS members and operational procedures. Between 1933 and 1939, the SD was administered as an independent SS office, after which it was transferred to the authority of the Reich Main Security Office , as one of its seven departments/offices. Its first director, Reinhard Heydrich, intended for the SD to bring every single individual within the Third Reich's reach under "continuous supervision".
Following Germany's defeat in World War II, the tribunal at the Nuremberg Trials declared the SD a criminal organisation, along with the rest of Heydrich's RSHA both individually and as branches of the SS in the collective. Heydrich's successor, Ernst Kaltenbrunner, was convicted of war crimes and crimes against humanity at the Nuremberg trials, sentenced to death and hanged in 1946.

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