Background: Prospective studies show that the adult outcomes of adolescents who deliberately harm themselves are marked by high rates of adversity and psychiatric disorders. The goal of this study was to identify pathways linking childhood risk factors to early adult outcomes of suicidal adolescents. Methods: A clinical sample of 158 adolescents who deliberately poisoned themselves was followed up six years later. Eighty per cent of the cohort (n = 126) were interviewed in early adulthood using a battery of standardised measures of psychopathology and social functioning. Results: Multivariate mediation path analysis identified four pathways linking child and adolescent risk factors to adverse outcomes in early adulthood. Family dysfunction, conduct disorder and hopelessness contributed to the risk of high adversity in early adulthood indirectly through its effect on other risk domains, including dropping out of school and adopting adult roles at a younger age. Hopelessness not only predicted dropping out of school but also independently contributed to the risk of chronic major depressive disorder in early adulthood. Child sexual abuse independently predicted high adversity and chronic major depression over and above the influence of hopelessness. Juvenile onset major depression independently predicted chronic major depression in early adulthood. A substantial proportion of the effects of child sexual abuse and hopelessness on the risk of deliberate self-harm in early adulthood was mediated by high adversity and the duration of major depression. However, chronic major depression was the only risk factor independently associated with deliberate self-harm in adulthood once correlation with adversity was taken into account. Conclusions: Chronic major depressive disorder is central to deliberate self-harm repetition. However, adult outcomes of suicidal adolescents are also dominated by the accumulating effects and consequences of other childhood risk factors, including child sexual abuse and adolescent hopelessness.