There is a sense in which every philosopher both constructs and confronts the philosophical universe in which their work takes form and has its effect. Plato's thought unfolds within the gravitational pull of the Greek city-state, the wandering sophists, the agonistic relations between Athenian aristocrats, and the massive presence of Socrates. Deleuze, to take a contemporary example, creates his concepts and embarks on his lines of flight between thinkers such as Nietzsche and Spinoza, artists and writers including Bacon, Lawrence, and Melville, and contemporary phenomena such as psychoanalysis and consumer capitalism. If we can speak of "Foucault's philosophy," it is in this sense of attempting to sketch out the philosophical universe in which Foucault's work and thought unfolds. What are the philosophical reference points that structure his thought? What are the questions and problems to which he tries to respond? How does he link up his thought with the actual concerns and struggles of both himself and others? The essays in this volume offer a series of answers to these questions, while this introduction attempts to give a preliminary overview of the terrain to be covered.