In order to examine the social transmission of prejudice in the military, attitudes and beliefs of Francophone (minority) and Anglophone (majority) prospective military ocers toward their own and other groups were assessed at the beginning and at the end of a four-year ocer-training program. Consistent with social dominance theory and system justi®cation theory, majority group members become signi®cantly more negative toward outgroups (e.g. Francophones, civilians and immigrants) and more likely to internalize beliefs that legitimize the economic gap between Francophones and Anglophones in Canada. Moreover, as predicted on the basis of self-categorization theory, the results show that identi®cation with the category `Canadian Forces Ocers' assessed at the midpoint in the program, moderates the change in intergroup attitudes and beliefs. Finally, minority group members did not internalize negative stereotypes of their own group. These results provide important evidence for the role of group socialization in the explanation of intergroup attitudes and beliefs and suggest that social identi®cation is a key factor in group socialization, consistent with selfcategorization theory.