Child abuse and neglect, often collectively called child maltreatment, are huge social problems affecting millions of children and adolescents in America. Adolescents are affected both by maltreatment which occurred during childhood with lingering effects and by maltreatment that continues into or begins in adolescence. Several decades of research indicate such maltreatment is associated with a number of mental health problems, including internalizing and externalizing problems, as well as other maladaptive developmental problems, in childhood and beyond. This is a review of research published from 2000 to 2010 with a specific focus on the nature and impact of child maltreatment on adolescent development. This article focuses on 3 especially critical themes of this recent research: (1) prospective longitudinal studies that examine adolescent adaptation and maladaptation of individuals abused or neglected earlier in life; (2) research that focuses on some developmental outcomes with particular salience during adolescence such as delinquency and substance abuse, romantic relationships, and sexuality; and (3) research that examined psychobiological processes in maltreated adolescents, processes that might indicate the mechanisms underlying maladaptive development.