Early experiences of physical and sexual abuse and parental neglect are risk factors for suicidal behavior in adolescence and adulthood. This article reviews the correlational, retrospective findings, emphasizing the more recent prospective and familial transmission studies that explore the factors mediating the relationship between childhood abuse/neglect and suicidal behavior. Related areas of research such as protective factors and the personality traits that are possible risk factors that mediate this relationship are reviewed. Research on the neurobiologic correlates of trauma that might have implications for understanding suicidal behavior is discussed, and several models for the study of the relationship between childhood adverse experiences and suicidal behavior are described.