The goal of this study was to identify the predictors and the moderators of group characteristics that influence deviancy and normative training processes in delinquent male adolescents. The authors experimentally tested the effects of group composition on deviant talk interaction processes among groups in which all members presented delinquent behaviors (“pure” delinquent group condition), those that included adolescents with no delinquent behaviors (“pure” normative group condition), and adolescents with both profiles (“mixed” group condition). Participants were 70 male adolescents aged 15–18 (M = 16.5; 56% Caucasian), with a random assignment to groups. Data were collected among three group sessions (T1, T2, T3), one session a week, using videotape. Two contents of interactions were also measured: antisocial and normative stories, counterbalanced across sessions. Results showed a significant group effect for antisocial talk and its reinforcement, with less antisocial talk within the mixed group condition in comparison to the pure delinquent group condition. The topic of interaction was also observed as a predictor of antisocial talk, with less normative interactions and more antisocial talk associated with antisocial topics. Finally, time moderated some relations between experimental groups and talk. We conclude with a discussion of the implications of this work for future research on deviancy training processes. Aggr. Behav. 39:30-44, 2013. © 2012 Wiley Periodicals, Inc.