The purpose of the present study was to examine how peer group processes of pressure and control and individual motivations for popularity would add to, and moderate the relationship between, childhood maltreatment and risky behavior in adolescence. A total of 1558 youth (804 girls) from three high schools in Ontario, Canada (M age = 15.02 years, SD = 0.86) reported on their alcohol use, delinquent behavior, childhood experiences of physical and emotional maltreatment and neglect, peer group processes involving control and individual popularity motivations. Regression analyses showed that, beyond the significant contributions of childhood maltreatment, peer group control predicted risky alcohol use and delinquent behavior. Peer group control and popularity motivations exacerbated the negative effect of physical maltreatment on delinquent behavior. Boys' experiences of peer group control were more strongly linked to alcohol use and delinquent behavior than girls'. These results suggest that there is a significant window of opportunity during adolescence where the peer group context can exacerbate or buffer childhood experiences.