"Sicherheitsdienst (German: [ˈzɪçɐhaɪtsˌdiːnst], Security Service), full title Sicherheitsdienst des Reichsführers-SS (Security Service of the Reichsführer-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 (formed in 1933) 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 (Reichssicherheitshauptamt; RSHA), 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"." - (en.wikipedia.org 30.01.2020)
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