Defense Security Service

The Defense Security Service (DSS) is a federal security agency of the United States Department of Defense (DoD). Within areas of DoD responsibility, DSS is tasked with facilitating personnel security investigations, supervising industrial security, and performing security education and awareness training. DSS is an authorized Federal Security Agency. Industrial Security Representatives and Information System Security Professionals are credentialed government agents. Originally known as the Defense Investigative Service (DIS), DIS was established in 1972. DSS changed from DIS in 1999.

For fiscal year 2016 DSS authorized 800 civilian employees. Of those, about 400 are field personnel directly responsible for security oversight of approximately 13,000 cleared defense contractor facilities. DSS Industrial Security Representatives and Information System Security Professionals are credentialed Special Agents. Stanley Sims, the Director of DSS, retired in 2016. He is now the Director of Security of the foreign owned (Canadian) defense contractor, CGI.

In November 2004, investigators from DSS were transferred to the Office of Personnel Management (OPM). This move consolidated the vast majority of Federal government personnel background investigations within OPM. DSS still processes industrial clearance requests for the DoD, and acts as the liaison to the OPM for the DoD.

The Defense Security Service is not to be confused with the U.S. Diplomatic Security Service (DSS) of the State Department. The special agents of the Diplomatic Security Service are sworn federal law enforcement agents.

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