In this collection of essays, Theda Skocpol, author of the award-winning book States and Social Revolutions (1979), updates her arguments about social revolutions. How are we to understand recent revolutionary upheavals in countries across the globe? Why have social revolutions happened in some countries, but not in others that seem similar? Skocpol shows how she and other scholars have used ideas about states and societies to identify the particular types of regimes that are susceptible to the growth of revolutionary movements and vulnerable to transfers of state power to revolutionary challengers. Skocpol engages in thoughtful dialogue with critics, and she suggests how culture and ideology can properly be incorporated into historical and comparative studies. She also vigorously defends the value of an institutionalist, comparative and historical approach against recent challenges from Marxists, rational choice theorists, and culturally oriented interpreters of particular revolutions.