Social Identity Theory is an influential concept in social psychology that explains how an individual’s self-concept and identity are shaped by their membership in a group. Developed by Henri Tajfel and John Turner in the 1970s, Social Identity Theory argues that people categorize themselves into different social groups, which then affects their behavior, attitudes, and beliefs.

What is Social Identity Theory?

According to Social Identity Theory, people tend to categorize themselves based on certain characteristics such as age, gender, race, religion, occupation or nationality. A person’s self-concept is not only influenced by their individual attributes but also by the social groups they belong to. For instance, if a person identifies themselves as a student of a particular college or university, they are more likely to behave and think in ways that align with the norms and values of that group.

Three Key Components

Social Identity Theory comprises three key components:

In-Group/Out-Group Bias

One of the main consequences of Social Identity Theory is In-group/Out-group bias. People tend to have more positive attitudes towards members of their own group (in-group) compared to members of other groups (out-group). This can lead to prejudice and discrimination towards out-groups.

Real-World Example

A real-world example of this theory can be seen during sports events where fans of a particular team or country identify themselves as part of that group. They behave and think in ways that align with the norms and values of their group, such as wearing team colors or waving flags. They also tend to show more support for their group compared to the opposing team or fans.


Social Identity Theory helps explain how our social identities affect our behavior, attitudes, and beliefs. By understanding how people categorize themselves into different social groups, we can better understand the dynamics of intergroup relations. It is important to recognize the potential for prejudice and discrimination that can result from In-group/Out-group bias and work towards promoting inclusivity and diversity.