Hank Johnston is Associate Professor of Sociology at San Diego State University. He is the founding editor of Mobilization , a journal of research in social and political movements, ranked as a top–ten journal in sociology.

Social movements play a central role in the scope and direction of social change. They were instrumental in the creation of the modern state and, today, are major forces in politics and culture. Environmentalism, gay rights, alterglobalization, and Islamic fundamentalism are all movements with far-reaching impacts on contemporary society. "What is a Social Movement?" traces how the study of movements such as these - of their structures, their ideas, and their repertoires of protest - have grown in recent years to become a major focus in the social sciences. It deftly navigates the organizational, ideational, and cultural complexity of political and social movements, and offers a succinct but comprehensive overview of the hows, whys, and wheretofores of studying them. The book analyzes how politics and culture frequently intersect as people participate in movements that call for change and pursue group interests. By focusing on movement organizations and networks, on what they do, and how they articulate their ideas of justice and collective interests, "What is a Social Movement?" lays the essential groundwork for understanding this significant and exciting field of research, where it came from, and where it is headed.