We have seen that social categorization is a basic part of human nature and one that helps us to simplify our social worlds, to draw quick if potentially inaccurate conclusions about others, and to feel good about ourselves. In many cases, our preferences for ingroups may be relatively harmless—we may prefer to socialize with people who share our race or ethnicity for instance, but without particularly disliking the others. But categorizing others may also lead to prejudice and discrimination, and it may even do so without our awareness. Because prejudice and discrimination are so harmful to so many people, we must all work to get beyond them.

Discrimination influences the daily life of its victims in areas such as employment, income, financial opportunities, housing and educational opportunities, and medical care. 

Having summarised some of the important theoretical contributions to prejudice-reduction, I will now present a summary of the main types of interventions with evidence on effectiveness, drawing on case studies and suggesting some principles which may be usefully applied elsewhere. Again it is vital to note that the case studies are not intended to be directly applicable to prejudice-reduction in Scotland. For instance, some of them talk about successful interventions to improve intergroup relations in post-conflict societies, which may be dealing with tensions that often spills over into actual (violent) conflict, and we may also assume that these are likely to be more 'reactive' than preventative. However, it may be appropriate to apply some of the 'universal principles' emerging from these to future strategies.

A mixture of lab-based interventions and evaluations of prejudice-reduction initiatives 'in the field' make up the growing literature on 'what works', however the majority of studies are controlled and experimental, have taken place in psychology laboratories, and often with psychology students as participants. Fewer studies take place in 'real-life', in schools or communities for example.