Do you have Double Top Secret Security Clearance? If so, you've likely been investigated by the Defense Security Service (DSS). A Department of Defense agency, the DSS provides the military services, Defense agencies, 27 federal agencies and approximately 13,500 cleared contractor facilities with security support services. Other DSS employees are National Industrial Security Program (NISP) representatives who manage classified contractor facilities. The DSS, established in 1972 as the Defense Investigative Service, employs more than 840 personnel and has an annual budget of $551 million.