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Seal of the United States Diplomatic Security Service

Seal of the DSS.

The U.S. Diplomatic Security Service (DSS or DS) is the federal law enforcement and security arm of the United States Department of State. The organization was formed in 1985 as the DSS; prior to this, it was called the Office of Security. The DSS is the lead U.S. law enforcement organization abroad, and is the most widely represented law enforcement agency in the world. Its duties include protecting U.S. diplomatic missions, U.S. diplomats, and visiting foreign dignitaries; conducting criminal, counter-terrorism, and counterintelligence investigations abroad; advising U.S. ambassadors on security matters; and managing or implementing security programs worldwide.