We review psychological research on intergroup conflict. First, we outline psychological perspectives on forms and functions of groups. Second, we present the most influential psychological theories of intergroup conflict and describe their similarities and differences in predicting individual prejudice, discrimination, and conflict engagement. Third, we review popular measures of intergroup discrimination, including rating measures, behavioral measures, and allocation tasks. Furthermore, we call for a refined semantic framework to structure and differentiate between different measures of intergroup bias. Fourth, we highlight several interventions that can de-bias intergroup relations and facilitate conflict resolution. Lastly, we propose that research on the psychology of intergroup conflict may benefit from a stronger interdisciplinary orientation regarding both theoretical perspectives and methods used and point out promising avenues for future research.