Stasi, official name Ministerium für Staatsicherheit (German: “Ministry for State Security”), secret police agency of the German Democratic Republic (East Germany). The Stasi was one of the most hated and feared institutions of the East German communist government.

The Stasi developed out of the internal security and police apparatus established in the Soviet zone of occupation in Germany after World War II. The law establishing the ministry, whose forerunner was the Kommissariat 5 (modeled along the lines of the Soviet KGB), was passed by the East German legislature on February 8, 1950, four months after the establishment of the German Democratic Republic. The Stasi, whose formal role was not defined in the legislation, was responsible for both domestic political surveillance and foreign espionage, and it was overseen by the ruling Socialist Unity Party. Its staff was at first quite small, and its chief responsibilities were counterintelligence against Western agents and the suppression of the last vestiges of Nazism. Soon, however, the Stasi became known for kidnapping former East German officials who had fled the country; many of those who were forcibly returned were executed.