Much of the literature on social movements focuses upon the determinants of participation. Why do some people with certain characteristics participate, while others who seem similar do not? How are some successful social movements able to generate involvement from bystanders and transform this potential into activism and, even harder, long time commitment, while other movements burn out? Clearly, social movements that endure for any length of time take on an organizational framework, morphing into social movement organizations (SMOs). SMOs appropriate many of the features and so share many of the advantages of formal organizations, including a known location and group of participants, recognition as a more or less legitimate player, and some continuity of mission and routines. By the same token, SMOs share many of the problems of other formal organizations. How is organizational authority sustained, especially as leaders turn over? What resources – financial, human, technical – are critical, and how are they combined across different SMOs? What is the division of labor between professionals and nonprofessionals, between staff and volunteers? How are SMOs organized across large geographical and geopolitical boundaries? How do they change over time? How do different SMOs sharing related goals that are part of the same movement (e.g., the environmental movement or the women's movement) cooperate, compete, and conflict with each other?

As we noted in the Preface, a concern with the organizational side of social movements goes back at least to the beginning of the last century.