DAVID A. SNOW, PhD, is Distinguished Professor of Sociology at the University of California, Irvine, USA.

SARAH A. SOULE, PhD, is the Morgridge Professor of Organizational Behavior at the Graduate School of Business, Stanford University, USA.

HANSPETER KRIESI, PhD, holds the Stein Rokkan Chair in Comparative Politics at the European University Institute in Florence, Italy, and is the principal investigator of the ERC Advanced Grant, Political Conflict in the Shadow of the Great Recession.

HOLLY J. MCCAMMON, PhD, is Cornelius Vanderbilt Professor of Sociology at Vanderbilt University, USA.