Since Stalin's death in 1953, Russia's leaders have every four or five years convened the nominally supreme body of the Soviet Communist Party, its Congress, to ratify policy guidelines and power shifts. Khrushchev lent excitement to the Congresses he presided over, launching surprise attacks on domestic and foreign Communists who were critical of his unorthodox traits. At the 20th Congress in 1956, the Party First Secretary went beyond the text of an anti-Stalin report that had earlier been agreed upon in the Kremlin and he implicated rival associates in cases of Stalinist misrule. The same foes, eliminated from high places in 1957, were just as suddenly brought under heavy criticism by Khrushchev's group at the extraordinary 21st Congress in 1959 and the 22nd Congress in 1961. A delegation of observers from Communist China headed by Premier Chou En-lai walked out of the 22nd Congress after their Albanian clients were unexpectedly assailed for heretical beliefs close to those held in Peking. In contrast, dramatic challenges and disclosures were missing from the 23rd Congress, which the successors of Khrushchev organized in 1966. The flat nature of the proceedings underlined the fact that a cycle of renewal in post-Stalin politics had been superseded by what was essentially a cycle of consolidation.