Despite thinking of themselves as democratic citizens, most individuals in contemporary, Western democracies—whether through direct action, representation, discourse, or any other means—have little to no actual say over political outcomes. They are ruled, but do not rule. Still, these citizens remain in a political culture largely structured by democratic norms and assumptions, one which encourages citizens to act as if they exercise political power, even when it is clear that they do not. Building on a substantial body of empirical literature that repeatedly demonstrates the political insignificance of ordinary citizens, this introductory chapter proposes that these citizens no longer live in a democracy, but a “post-democracy.” After briefly describing how thinkers like Colin Crouch and Jacques Rancière have employed the concept, this chapter emphasizes the extent to which we still lack a common definition, as well as any sustained attention to the broader implications of a post-democratic diagnosis. The chapter then ends by outlining the way in which this book will remedy these deficiencies and develop a robust, comprehensive theory of post-democratic political life.