The study of prejudice is a major theme in social psychology because it encompasses or has close ties to many different core areas in the field: in particular, research and theorizing in this area is not only related to intergroup relations but also attitudes, group processes, social cognition, and social perception. This new four-volume major work brings together papers documenting the most important advances in both theorizing and methodology related to this field, to highlight the contributions of social psychology to better understanding intergroup biases. These volumes include not only articles and book chapters related to the classic research in this area but also papers detailing the major advances in methodology and theorizing that have been made through the years. By bringing together papers from diverse theoretical perspectives and methodological approaches, this collection will allow students and scholars will be able to better appreciate the broad range of this knowledge. Volume One: Introduction Volume Two: Social Categorization Processes Volume Three: Stereotyping, Prejudice, and Discrimination Volume Four: Strategies to Reduce Intergroup Biases