Group Processes and Intergroup Relations is a contemporary, accessible introduction to the social psychological study of groups. Covering international research, both classic and cutting edge, this dynamic new textbook forms a complete and coherent course in this field. Coverage moves from defining groups and their formation, to group performance and leadership, to crowd behaviour and prosocial behaviour. The authors give a broad perspective on groups, from discussions of group performance and social influence to representations of social categories and stereotypes, prejudice and intergroup discrimination, stigmatization and social exclusion. Concluding chapters focus on developing interventions for improving intergroup relations and discuss ways of thinking about groups in societies and across cultures, encompassing multiculturalism and diversity.