Efforts to prevent family violence have focused on specific family subsystems, most notably intimate partner violence (IPV) and child abuse. Intensive programs that reduce normative acceptance of violence and enhance conflict‐management skills have successfully prevented IPV in both universal and high‐risk samples of high‐school‐aged youth. Dyadic interventions for adult couples have not been consistently effective in preventing IPV. For child abuse, significant preventive effects have been found for nurse home visiting, early Head Start, and Triple P, a multilevel public health approach to promoting positive parenting. Parent–Child Interaction Therapy, which uses live coaching to enhance parenting skills, has been effective in preventing new instances of aggression among maltreating parents. Despite evidence that aggression and violence are common in other family subsystems, including sibling aggression, child‐to‐parent aggression, and extended family aggression, our review found no controlled studies of interventions focused on preventing violence in entire family units.