In analysing the major contributions of social psychology to the topic it is possible to distinguish between three approaches. These are: there are those that locate the cause of prejudice in the psychological make-up of the individual; there are approaches that emphasise the role that external or environmental factors play; and finally, there are approaches in which group membership itself is seen as critically important. Although there has been little discernible improvement in social relations across the globe, there have been considerable advances in our understanding of the causes of prejudice and intergroup conflict. Some psychologists believe that people who display prejudice differ in personality from non-prejudiced people. As a complete explanation of intergroup prejudice, then, belief-congruence theory is probably inadequate in its original form. Some theories of prejudice emphasize the role of cognitive processes in the formation and maintenance of negative group stereotypes. The various approaches have direct implications for the reduction of prejudice and the resolution of conflict.