Key Theoretical Frameworks Social Identity Theory Originally formulated by social psychologists Henri Tajfel and John Turner in the late 1970s, Social Identity Theory explains how individuals define themselves in terms of group memberships and how this influences their behaviour towards in-group (their own group) and out-group (other groups) members. According to Tajfel and Turner, a person’s self-concept has a significant social component: people derive pride, self-esteem and norms from the groups to which they belong. Key concepts include: In-group vs. Out-group: People categorise themselves and others into groups, leading to in-group favouritism and sometimes out-group discrimination. For example, employees in one department may develop a strong in-group identity, subtly competing with other departments. Social Categorisation and Comparison: Individuals strive for a positive social identity by comparing their group favourably against others. If an in-group’s status is low, member...