David A. Snow is a Distinguished Professor of Sociology at the University of California, Irvine, where he also serves as the Co-Director of the Center for Citizen's Peacebuilding. He is the author of The Wiley-Blackwell Companion to Social Movements (with Sarah Soule and Hanspeter Kriesi, 2004), Social Movements: Readings on Their Emergence, Mobilization, and Dynamics (with Doug McAdam, 2009), and A Primer on Social Movements (with Sarah Soule, 2010). Professor Snow was the 2008 recipient of the Society for the Study of Social Problems' Lee Founders Award for career contributions to the study of social problems.

Donatella della Porta lectures at the European University Institute, Florence, and directs the ERC project ‘Mobilizing for Democracy: Democratization processes and the mobilization of civil society’. She is the co-author of Social Movements: An Introduction (with Mario Diani, 2006); Europeanization and Social Movements (with Manuela Caiani, 2009); and Mobilizing on the Extreme Right: Germany, Italy, and the United States (with Manuela Caiani and Claudius Wagemann, 2012); and editor of Democracy in Social Movements (2009); Another Europe (2009). In 2011, Professor della Porta was awarded the Mattei Dogan Prize for political sociology.

Bert Klandermans is Professor in Applied Social Psychology at the VU University of Amsterdam. He is Director of the research program Social Conflict and Change. He is the editor and co-author of Methods of Social Movement Research (with Suzanne Staggenborg, 2002) and Extreme Right Activists in Europe (with Nonna Mayer, 2006). He also co-edited the Handbook of Social Movements across Disciplines (with Conny Roggeband, 2007). In 2011/2012 he was President of the International Society of Political Psychology. In 2009 he received a Royal Award for his efforts to link science and society.

Doug McAdam is Professor of Sociology and Director of the Program on Urban Studies at Stanford University. He is widely credited as one of the pioneers of the political process model in social movement analysis. His publications include Political Process and the Development of Black Insurgency, 1930-1970 (1982), Freedom Summer (1988), Dynamics of Contention (with Sid Tarrow and Charles Tilly, 2001), and Putting Social Movements in their Place: Explaining Opposition to Energy Projects in the United States, 2000-2005 (with Hilary Boudet, 2012).