Research on determinants of adolescents’ images or prototypes of drinking peers has demonstrated that parents and peers can influence the formation of drinker prototypes. It has also been shown that drinker prototypes mediate relations between peer and parental drinking behaviors and norms, and adolescent alcohol use. The current study examined this issue by taking into account the reciprocal relationship between drinker prototypes and alcohol consumption. Furthermore, these issues were studied for adolescents with and without drinking experience. For this purpose, longitudinal data were gathered among 1956 Dutch adolescents (12–16 years). Structural modeling analyses revealed significant effects of drinker prototypes on future alcohol use among both abstaining and drinking adolescents. Among drinking adolescents, the impact of peer and parental norms on adolescents’ alcohol use was mediated by drinker prototypes. Among adolescents with no drinking experience, drinker prototypes also affected future alcohol use. However, these effects were less important than the direct impact of peer and parental drinking. In sum, the present study revealed that prototypes mediate the influence of peer and parental norms on adolescents’ alcohol use, but only in adolescents who already have drinking experience. Implications of these findings are discussed.