AbstractThe study of communist regime legitimacy. Most theories on the fall of communism focus on non-ideological factors. An approach with a potential to make visible also the ontological crisis of Marxism-leninism is the study of communist regime legitimacy. This paper reviews Max Weber's and David Beetham's respective theories on the legitimition of power. It presents the mainly Weber-inspired research on political legitimacy that was conducted by Western scholars of the communist world and goes on to argue that the Weber-typology has very little to offer if one wants to render intelligible the ideological aspects to the demise of communism. With Beetham's theory as a point of departure, and with references to other students of Marxism-Leninism, the paper tries to show how ideology can be seen as a manifest, active and limiting factor in the former communist systems and that it is possible to study the fall of communism focusing on ideology and political legitimacy.