The KGB was the chief government intelligence and security agency of the Soviet Union from 1954 until its collapse in 1991. It was responsible for foreign intelligence, domestic security, and the general surveillance of the population. The KGB was feared by foreign countries because of its reputation for being one of the largest and most formidable government organizations during the Cold War. The KGB consisted of two parts: intelligence services and military units that were totally separate from each other. The KGB was known for its ability to infiltrate spies into target countries and gather information. The KGB was also responsible for monitoring and suppressing internal dissidents. The KGB was dissolved in 1991 after the collapse of the Soviet Union.