Taking an analytic and historical approach, this work develops and defends Althusserian critical theory. This theory, it is argued, produces knowledge of how a particular class of people, in a particular time, in a particular place, is dominated, oppressed, or exploited. Moreover, without relying on a general notion of human emancipation, concrete critical theory can suggest political means for the alleviation of these conditions. Because it puts Althusser's ideas in dialogue with contemporary social science and philosophy, the book as a whole makes contributions to Althusser studies, to Anglo-American political philosophy, and to current debates in the philosophy of the social sciences.