Predictors of youth religiosity were developed from eight domains: childhood training, religious schooling, cognitive ability, psychodynamic need, parenting style, role models, family life cycle, and background demographics. Data are from the National Survey of Children (NSC). Predictors were assessed when participants were 7–11 and 11–16 years of age. Religiosity was assessed when participants were 17–22 years (N = 1,046). After identifying the best predictors within a domain, an across-domain regression analysis was conducted to determine the predictors' relative contributions. The best predictors of youth religiosity were ethnicity and peers' church attendance during high school. Other predictors were, in order of decreasing magnitude: residence in the south, gender, religious schooling during childhood, maternal religiosity, church attendance during childhood, the importance mothers placed on childhood religious training, and an interaction variable identifying religious mothers who were very supportive. These analyses attest to the primacy of religious role models in the development of youth religiosity.