SS - formed in 1925, led by Heinrich Himmler after 1929. It rose from 50,000 members in 1934 to over 1,000,000 in 1944. They showed total obedience to Hitler . They were highly trained and expected to be pure Aryans. (north-western Europeans, specifically with blue eyes and blonde hair, superior race.) Primary responsibilities; destroy opposition and carry out Nazi racial policies. Death's Head units - ran concentration and extermination camps. SD - investigated disloyalty. Waffen SS - special armoured regiments that fought alongside the regular army.