What does protest means in industrial societies? To answer this question, David Meyer and Sidney Tarrow bring together political scientists and sociologists from Europe and the United States to build on comparative insights. The 17 contributors include some of the most prominent voices in the study of contentious politics as well as a few new ones. Some chapters are organized around case studies (Klandermans, Roefs, and Olivier on the African National Congress; Rucht on protest in Germany; and McCarthy and McPhail on protest in the United States), while others compare across cases (Crozat on Western democracies; Della Porta, Fillieule, and Reiter on policing in France and Italy; Kubik on Central Europe; Hipsher on Latin America). The editors' introduction and the final two chapters (Katzenstein on feminist movements; Keck and Sikkink on transnational advocacy networks) advance cross-regional comparisons.