Beyond cases reported to authorities, little knowledge exists on the types, amount, and effects of childhood victimization. Using the National Survey of Adolescents, researchers examined the prevalence of sexual assault, physical assault, physically abusive punishment, and witnessing an act of violence and subsequent effects on mental health, substance use, and delinquent behavior problems. The study found that youth victimization is clearly linked to mental health problems and delinquent behavior. Results are analyzed across gender and race/ethnicity and translated into national estimates.