This book examines how sameness and difference are negotiated within social movements.Movements for social change are by their nature oppositional, as are those who join change movements. How people negotiate identity within social movements is one of the central concerns in the field. This volume offers new scholarship that explores issues of diversity and uniformity among social movement participants. Featuring case studies that range widely-from Jewish resistance fighters in Nazi-occupied Poland to antigay Christian movements in the United States to online white supremacy groups-the essays show how participants set aside issues of personal identity in order to merge together and how these processes affect mobilization and the attainment of goals.