Fifty-odd years of inter-group contact: from hypothesis to integrated theory.

We review 50-odd years of research on Allport's (1954)'contact hypothesis', to assess progress, problems, and prospects. We chart the progress that has been made in understanding two distinct forms of contact: direct and indirect. We highlight the progress made in understanding the effects of each type of contact, as well as both moderating and mediating factors, and emphasize the multiple impacts of direct contact, especially.