A review of theoretical issues in the study of peer influence and deviance reveals two competing conceptions of peer group influence. One perspective focuses on identification with the group as individual attitudes become a function of group norms. Another theory is that the desire to be favorably evaluated by the group determines peer influence, which in turn depends on group standards of evaluation. These theories were tested with male adjudicated delinquents in four institutions. Residents of these institutions live in groups of 9-12 members, who participate in all activities together, having little contact with other groups. Forty-five groups participated in the research, with 313 subjects providing data. Data on group norms came from questionnaires completed by all group members. Respondents supplied data upon entering the group and after participating in the group 4 months. The group norms were measured before the respondent had an opportunity to influence the group. The model used also includes respondents' perceptions about the group. Study findings are supportive of peer influence as stemming from desire for favorable evaluation by the peer group. All groups held standards for group member evaluation that favored support for institutional goals, such that group members' desire to be favorably evaluated in the group does serve institutional goals. 3 figures and 19 references.