Intergroup Behaviour Introduction Intergroup behaviour refers to how individuals or groups of people interact with and relate to one another based on their membership in different social categories such as race, ethnicity, gender, nationality, or religion. This field of study has long been of interest to social psychologists as intergroup behaviour has the potential to lead to both cooperation and conflict. Social Identity Theory One of the most well-known theories of intergroup behaviour is Social Identity Theory, which was first proposed by Henri Tajfel and John Turner in the 1970s. According to this theory, individuals derive a sense of self from their membership in social categories or "ingroups." Social identity theory suggests that individuals are motivated to enhance the positive image of their ingroups, leading them to act in ways that benefit their ingroups, while negatively evaluating "outgroups" that do not belong to their ingroup. This can result in inte