The relevance of sociological theory for explaining the recent dramatic changes in Eastern Europe is at hand. The impact of the downfall of communism has been compared with those "Great Transformations" along which sociology evolved as a "science of crisis par excellence" (Habermas). The actual elaboration of a sociological theory of post-communist transformation and its relation to East European studies is, nevertheless, anything but clear. The unexpected collapse of socialism was perceived as a failure of prognosis and led to self-critical debates in all social science disciplines. In this rethinking its basic concepts, sociology is exposed to pressure from different sides -above all from the polemic launched with the surprising revival of the theory of totalitarianism against the ,,liberalist social sciences" across the board. Influential historians like Robert Pipes, Martin Malia, Robert Conquest, and Francois Furet followed by sociologists from Robert Nisbet to Seymour Lipset hold the fatal influence exerted by social science concepts on Eastern European and Soviet Studies during the last decades responsible for the "whole intellectual disaster in Western Academe" which became apparent after 1989. These approaches, as the neo-totalitarian accusation runs, elevated Soviet socialism to a modernization strategy and conceded a reform capacity which, in fact, was not available. Target of this critique are all attempts of a social history "from below", sociological theories of action and especially "the positivist illusion of modernization theory". Blinded by political motives, it is said, the insights of (neo-)totalitarianism theory into the inevitable collapse of communism were dismissed.