Social Identity Theory

What is it?

Social identity refers to an individual’s knowledge that he belongs to some kind of group, where membership of this group is associated with emotional significance (Tajfel 1974). The concept of social identity is defined as “that part of an individual's self-concept which derives from his knowledge of his membership of a social group (or groups) together with the emotional significance attached to that membership” (Tajfel, 1974: 69). 

The core premise of the theory is that in social situations people think of themselves as group members rather than as unique individuals. It underpins group behaviour and sees this as qualitatively different from interpersonal behaviour. The more strongly a person identifies with their social group, the more likely they are to abide by the rules and behaviours demonstrated by this group.

Two motivational factors within the social identity literature are highly relevant to the science of behavioural change. These motivations are known as self-enhancement and uncertainty-reduction.

  1. Self-enhancement surrounds the belief that ‘we’ are better than ‘them’, reflecting the need for a group to maximise its status, prestige, and social valence. The self-enhancement motive, therefore, guides the need for positive social identity and represents a powerful driver of behaviour. The Tully grower, for example, may respond favourably to performing behaviours that demonstrate his district is superior to Innisfail.

  2. The uncertainty-reduction motive rests on the premise that group identification is one of the most effective ways of reducing uncertainty about oneself. Group identification, therefore, furnishes clear group prototypes that prescribe how we ought to behave and, as result, is one of the most powerful methods of modifying behaviours of individuals.

Social identity is a major determinant of (a) effective communication (Morton, Wright, Peters, Reynolds, & Haslam, 2012), (b) workplace motivation (Ellemers, De Gilder, & Haslam, 2004), (c) organizational citizenship behaviour (van Dick, Grojean, Christ, & Wieseke, 2006), (d) social support and stress (van Dick & Haslam, 2012), and (e) leadership (Ellemers et al., 2004; Hogg, 2001; Reicher, Haslam, & Hopkins, 2005; Turner & Haslam, 2001; van Knippenberg & Hogg, 2003).


How could you apply this theory?

Social identities provide a framework for how people view the world and how they act. It is the primary determinant of social perceptions and social behaviours.

Social identity theory applied:

  • Communicate messages to a group through their leader/s.

  • Identify people's social identities and use them to your advantage - don't threaten them

  • Create or change social norms associated with social identities. i.e. Change the norms of a group by utilising social identity.

  • Look to the groups that people belong to, to understand their beliefs and behaviour and where they originate

  • Frame things in terms of groups to appeal to peoples social identities.

  • Enhance the image of the groups people belong to and you will also enhance their own self-image

Example of the theory applied

By encouraging growers to engage more within the cane growing community, their social identity as a canegrower in the community is enhanced, and efforts to extend innovation and increase the uptake of best management farming practices within the cane industry may be strengthened. "This is because feeling part of a community of canegrowers was associated with a desire to improve farming practices and an increased likelihood of rating the Queensland cane industry as innovative. Additionally, industry identity and feeling like growers could turn to other growers for advice were also both associated with ratings of Queensland cane industry innovation. Previous studies have shown similar links between participation in community activities and BMP adoption (Emtage & Herbohn 2012)" - Pickering et al., 2018.

Why is this theory important for behaviour change?

A persons actions and beliefs are informed by the social groups that they belong to. Appealing to social identities or using the identities as a tool to promote a new social norm can be an effective way to change behaviour.

A cane grower’s sense of identity as a grower, especially in their connection to a specific geographical region, may be an important influence upon their ongoing willingness to adopt new farming practices.


Tajfel, H., & Turner, J. C. (1979). An integrative theory of intergroup conflict. In W. G. Austin & S. Worchel (Eds.), The social psychology of intergroup relations. Monterey, CA: Brooks/Cole.

Related Concepts

Self-categorisation theory

Group polarisation theory

Stereotype threat