This is an updated and edited version of Robin Marris' classicThe Economic Theory of Managerial Capitalism (1964). This was widely recognized as pathbreaking as it was the first attempt by a professional economist to make a formal theory of the behavior and growth of a large-scale "managerial" corporation based on a realistic assessment of the sociological and institutional environment. The model determined the long run growth rates of individual firms on the basis of the financial and market environment on the one hand, and the needs, interest and aspirations of both managers and shareholders on the other. Managers in particular were shown to trade desire for growth against fear of takeover. These then novel important features of modern capitalism--mergers, takeovers and executive bonuses and the relationship between the growth of firms and the growth of the economy--have become increasingly topical. The new book contains the original introduction along with reworked and updated coverage of the theoretical model, along with completely new chapters both of micro-theory and assessing and responding to the debate which the book created.