Social movements have wrought dramatic changes upon American society. This observation necessarily raises the question: Why do some movements succeed in their endeavors while others fail? This book answers this question by introducing an analytical framework that begins with a shift in emphasis away from the characteristics of movements toward the targets of protests and affected bystanders, their interests, and why they respond as they do. Such a shift brings into focus how targets and other interests assess both their exposure to movement disruptions as well as the costs of conceding to movement demands. From this vantage point, diverse outcomes stem not only from a movement’s capabilities for protest but also from differences among targets and others in their vulnerability to disruption and the substance of movement goals. Applied to the civil rights movement, this approach recasts conventional accounts of the movement’s outcome in local struggles and national politics, and also clarifies the broader logic of social change.