Physicalism is a programme for building a unified system of knowledge based on the view that everything is a manifestation of the physical aspects of existence. Jeffrey Poland presents a comprehensive exploration of the philosophical foundations of this programme. He investigates the core ideas, motivating values, and presuppositions of physicalism; the constraints upon an adequate formulation of physicalist doctrine; the epistemological and modal status, the scope, and the methodological roles of physicalist principles. He reviews and evaluates major objections to the programme, and considers its significance for philosophy, science, society, and individual persons. An important theme of the book is that recent attempts to formulate a `non-reductive' version of physicalism are inadequate and that the role of supervenience relations in expressions of physicalist thought is significantly limited.This is the first sustained and systematic discussion of the major philosophical aspects of the physicalist programme. Professor Poland also examines the relations between physicalism and other philosophical positions, such as realism, empiricism, and relativism, and suggests that physicalism is compatible with a tolerant pluralism in the philosophical, cultural, and personal domains.