Nadharia tete ya mgusano (kwa Kiingereza: "Contact Hypothesis") inasema kwamba ili kuboresha uhusiano kati ya vikundi viwili njia ni kuanzisha mgusano kati yao. Gordon W Allport, The Nature of Prejudice, Reading, Mass : Addisson-Wesley, 1954 Rupert Brown, Prejudice, Its Social Psychology, Blackwell, Oxford UK et Cambridge USA, pages 236-270, 1995 Thomas F Pettigrew, Intergroup contact theory, Department of psychology, University of California, Santa Cruz, California, pages 65-85, 1998