Anarchist political philosophers normally include in their theories (or implicitly rely upon) a vision of a social life very different than the life experienced by most persons today. Theirs is a vision of autonomous, noncoercive, productive interaction among equals, liberated from and without need for distinctively political institutions, such as formal legal systems or governments or the state. This "positive" part of anarchist theories, this vision of the good social life, will be discussed only indirectly in this essay. Rather, I want to focus here on the "negative" side of anarchism, on its general critique of the state or its more limited critique of the specific kinds of political arrangements within which most residents of modern political societies live. Even more specifically, I will center my discussion on one particular version of this anarchist critique - the version that is part of the theory now commonly referred to as "philosophical anarchism". Philosophical anarchism has been much discussed by political philosophers in recent years. But it has not, I think, been very carefully defined or adequately understood. My object here will be to clear the ground for a fair evaluation of philosophical anarchism, by offering a more systematic account of the nature of the theory and of possible variants of the theory, and by responding to the most frequent objections to the theory. I hope by this effort to present philosophical anarchism as a more attractive, or at least a less obviously flawed, political philosophy.