The Waffen-SS grew from three regiments to over 38 divisions during World War II, and served alongside the Heer (regular army), Ordnungspolizei (uniformed police) and other security units. Originally, it was under the control of the SS Führungshauptamt (SS operational command office) beneath Reichsführer-SS Heinrich Himmler. With the start of World War II, tactical control was exercised by the High Command of the Armed Forces (OKW),[3] with some units being subordinated to Kommandostab Reichsführer-SS (Command Staff Reichsführer-SS) directly under Himmler's control.[4]