and how different risk and protective factors interact to influence the probability for suicidal behaviors and substance use. In the following sections, we first review specific risk factors of suicidal behavior and drug abuse, which includes impulse control and impulsive aggression, stressful life events, and prior substance use behavior, as well as serotonin dysregulation and other biological factors. Second, we present approaches to studying suicidality and substance use, the developmental and conceptual issues to consider, and the methods to conduct innovative longitudinal studies of these behaviors during adolescence. Third, we present a model of suicide (e.g. the stress-diathesis model of suicidal behavior; Mann et al. 1999; Mann, 2003), review features unique to adolescent development, and suggest extensions of the model that may help to explain how, when, and to what extent specific factors increase the risk for adolescent suicidal behavior and substance use.
