The extent to which positive alcohol expectancies mediated the association between delinquency and alcohol use, as well as whether age, sex, or race moderated this mediational relation, was examined in a population-based sample of Iowa schoolchildren (N = 85,301) from the 6th, 8th, and 11th grades. Positive alcohol expectancies were found to partially mediate the association between delinquency and alcohol use (alcohol use initiation, past-month drinking, and past-month binge drinking) across the full sample and in each age, sex, and racial subgroup. Evidence for moderated mediation was found for age and race but not for sex, which suggests that the magnitude of the relations among delinquency, positive alcohol expectancies, and alcohol involvement is different in younger versus older children and White, African American, Native American, Asian, and Hispanic youths but is similar in boys versus girls. (c) 2007 APA, all rights reserved.