Over the last three decades, researchers have made remarkable progress in creating and testing family-focused programs aimed at fostering the cognitive, affective, and behavioral health of children. These programs include universal interventions, such as those for expecting or new parents, and workshops for families whose children are entering adolescence, as well as programs targeted to especially challenged parents, such as low-income single teens about to have their first babies, or the parents of children with autism. Some family-focused programs have been shown to foster significantly better outcomes in children, including enhanced educational performance, and reduced rates of teen pregnancy, substance abuse, and child conduct and delinquency, as well as reduced child abuse. The favorable cost-benefit ratios of some of these programs are due, in part, to the multiple and far-ranging effects that family-focused prevention programs targeting children can have. Other family-focused programs have shown success in smaller academic studies but have not been widely applied, or have not worked as effectively or failed when applied to more diverse real-world settings. Strategies for Scaling Effective Family-Focused Preventive Interventions to Promote Children's Cognitive, Affective, and Behavioral Health is the summary of a workshop convened by the Institute of Medicine Forum on Promoting Children's Cognitive, Affective, and Behavioral Health to explore effective preventive interventions for youth that can modify risk and promote protective factors that are linked to mental, emotional, and behavioral health, and how to apply this existing knowledge. Based on the 2009 report Preventing Mental, Emotional, and Behavioral Disorders Among Young People, this report considers how to build a stronger research and practice base around the development and implementation of programs, practices, and policies that foster children's health and well-being across the country, while eng