The present research studied changes in stereotypes, attitudes and perceived variability of national groups within a sample of U.S. college students who spent one year studying in either West Germany1 or Great Britain. Subjects' stereotypes and attitudes toward host country members changed significantly during their stay, whereas attitudes and stereotypes toward control nationalities did not, and neither attitudes nor stereotypes further changed during the first nine months after subjects had returned home. On the other hand, perceptions of group variability changed significantly both during the stay and after departure from the host country. Although group perceptions generally became less positive over the course of the sojourn, these changes did not seem to be due to negative intergroup contact. Rather, the more contact students reported having with host country members the more positive were their attitudes and stereotypes of the groups. Results are discussed in terms of their implications for implementing student exchange programmes.