Understanding how youths develop particular styles of responding to stress is critical for promoting effective coping. This research examined the prospective, interactive contribution of maternal socialization of coping and peer stress to youth responses to peer stress. A sample of 144 early adolescents (mean age = 12.44 years, SD = 1.22) and their maternal caregivers completed questionnaires and semistructured interviews in 2 waves over a 1-year period. Results revealed that mothers' disengagement coping suggestions predicted maladaptive responses to stress, particularly for youths who received low levels of engagement suggestions, and engagement coping suggestions protected youths against maladaptive responses to stress. Importantly, these effects emerged only in the context of heightened peer stress. This research suggests that maternal socialization of coping has the potential to support or undermine youths' development of an effective repertoire of responses to stress. (Contains 2 tables and 3 figures.)