What was the difference between the KGB and the GRU?

The primary difference between the KGB and the GRU during the Soviet era lay in their scope and primary mandates.

• KGB (Committee for State Security): This agency functioned as the Soviet Union’s primary domestic and foreign intelligence service. Its broad responsibilities included internal security, domestic counterintelligence, surveillance of the population, protection of political leadership, and border control. It acted as the "sword and shield" of the Communist Party, often operating domestically against Soviet citizens.123
• GRU (Chief Intelligence Directorate): This was the chief intelligence directorate of the army general staff, focusing almost exclusively on military intelligence. Its operations centered on assessing the military capabilities of foreign rivals, acquiring military technology, and conducting sabotage or reconnaissance through specialized units known as spetsnaz.34

While both agencies operated internationally and occasionally experienced competition or conflict, the KGB was generally considered the dominant organization within the Soviet intelligence system. Unlike the KGB, which was dismantled and reorganized following the dissolution of the Soviet Union, the GRU remained largely intact.324