Abstract: The author examines the paradox of Mikhail Gorbachev's esteem for Lenin in combination with his growing rejection of Leninism. While Gorbachev still held the office of general secretary of the Soviet Communist Party, he embraced ideas fundamentally at odds with those of the Soviet Union's principal architect. The focus of Western writers on Gorbachev's 1987 book, Perestroika. New Thinking for Our Country and the World, as a major source has been simplistic and misleading, obscuring the radicalization of Gorbachev's political ideas from 1988 onward. Drawing, inter alia, on previously unused archival documents, the author demonstrates how Gorbachev's views moved closer to those of Eduard Bernstein, a democratic socialist thinker whom Lenin despised, than to Leninism. Given the institutional power Gorbachev wielded until late in the perestroika period, his embrace of concepts radically at odds with Leninism was of critical importance, opening doors which had remained firmly closed for decades. Keywords: Bernstein, Bolshevik, command-administrative system, democratization, Gorbachev, Lenin, Leninism, perestroika, pluralism, socialism In a highly authoritarian political system, with great power vested in the office at the top of the political hierarchy, the values, policy preferences, and personality of the holder of that office are liable to make a bigger difference to major policy outcomes than the personality, values, and preferences of the head of government within a democracy. The constraints on the latter will be far greater--not only from members of his her party, but also from opposition parties, the legislature, the judiciary, organized interests, and public opinion, to name the most obvious. That is not to say, however, that the power of the top leader in an authoritarian system is entirely unconstrained. If the authoritarian system is a) highly institutionalized and b) highly ideologized, then there are likely to be quite serious obstacles in the path of major innovation of even the topmost leader. In particular, it will be very risky for him (I do not add or her, for male leadership is ubiquitous in totalitarian and authoritarian regimes) to attempt to change the basic tenets of the system's legitimating ideology its institutional norms. These factors all apply to the case of Mikhail Gorbachev and the transformation of the Soviet system. When Gorbachev became general secretary of the Communist Party of the Soviet Union in March 1985, he attained the office which commanded greater institutional resources than any other within the country. Yet this was in a thoroughly consolidated authoritarian regime--in the classification of Linz and Stepan an example of post-totalitarianism (1)--in which the top leader was accorded great authority provided he played by the rules of the game. There was an important precedent in the post-Stalin Soviet Union illustrating the potential vulnerability of even the supreme leader. Although Nikita Khrushchev did not challenge the norms of the system to anything like the extent to which Gorbachev was subsequently to do, his frequent reorganizations of the party and state structures and an unwillingness to work through the established bureaucratic channels led to his removal from the leadership in October 1964 on the instigation of the leading members of the Politburo, (2) backed up by the Central Committee as a whole. (3) Gorbachev was always conscious of the fate of Khrushchev and of his need, therefore, to persuade other members of the ruling oligarchy to embark on far-reaching reform. He could not simply introduce radical change by fiat, although he had a power of appointment which enabled him gradually to change the composition of the top leadership team. Even that power was by no means unconstrained. Promotion to the highest executive committee within the system, the Politburo, was by a process of collective co-option, in which the pool of talent was restricted to people who were already members of the Central Committee (chosen at five-year intervals at party congresses). …