This paper develops an economic and social capital model linking single mothering in poverty to adolescent violence. Our model focuses on bonding social capital within parent-child relationships, negative social capital in delinquent peer groups, and bridging social capital residing in youths' friendship networks. Our research is the first to consider that the family experiences of adolescents' peers affect adolescent violence. We test hypotheses using the Add Health, finding that peer networks are a source of bridging social capital through which collective parenting helps explain youth violence as well as the links between family structural (dis)advantages and youth violence.