Original: Under the overall administration of the Schutzstaffel (SS), it was administered by the Reichssicherheitshauptamt (RSHA) ("Reich Main Security Office") and was considered a sister organization of the Sicherheitsdienst (SD) ("security service") and also a suboffice of the Sicherheitspolizei (SIPO) ("security police").
Simplified: Under the overall administration of the SS it was administered by the Reichssicherheitshauptamt and was considered a dual organization of the Sicherheitsdienst and also a suboffice of the SD.