USSR: Communist Party: 1917-1991 Leadership of the Communist Party Party Congresses Transitional period (1917-1919) Politburo of the Central Committee (1919-1952) Orgburo of the Central Committee Secretariat of the Central Committee Presidium of the Central Committee Politburo of the Central Committee (1966-1991) Last updated on: 25 Jun 2009 20:00:00