Using data from a nationally representative sample of American adult males (N = 2,512), this study examines (a) whether duration of membership in the Boy Scouts of America is associated with adult civic engagement and (b) whether five characteristics of positive youth development (confidence, competence, connection, character, and caring) account for the relationship between duration of Scouting membership and adult civic engagement. The results from structural equation modeling indicate that duration of participation in Scouting is positively associated with four indicators of civic engagement: community involvement, community volunteering, community activism, and environmental activism. Among the five positive characteristics, confidence and competence were found to fully mediate the effects of Scouting on all four types of civic engagement, whereas the other three only to partly mediate the effects