Book excerpt: Understanding Revolution concisely, but thoroughly, explains one of the most fundamental sources of political change in the modern world. Designed to be accessible to undergraduate students, the book systematically explores such questions as: What should be defined as a revolution? Is there a typical pattern to the course of a revolution? What are the roles of ideologies, structures (e.g., the state, class structures, the international system), and individuals in shaping revolutions? What causes groups to mobilize behind revolutionary leaders? What happens after a revolutionary group assumes power, or fails?The discussion highlights points of agreement and debate within the social science literature, and brief case studies of revolutions and revolutionary movements bring concepts to life.