The FSK (Federalnaya Sluzhba Kontrrazvedki (ФедераÌÐ»ÑŒÐ½Ð°Ñ Ð¡Ð»ÑƒÌжба КонтрразвеÌдки), Federal Counterintelligence Service) was a state security organization, initially of the USSR, and, after its dissolution, of the Russian Federation. The FSK was the successor organization to the KGB. It existed from 1991 to 1995, when it was reorganized into the FSB.