This article discusses the definition and classification of suicidal behaviors and reviews the epidemiologic, psychiatric, psychosocial, and biologic risk factors associated with adolescent suicide. In order to demonstrate the pathogenesis of suicidal behaviors, three conceptual models are presented, each emphasizing either stressful life events, psychiatric disturbances and biologic components, or individual vulnerabilities as the underlying factor to the inception of self-destructive behaviors. Each of these models demonstrates that a pattern of high risk and reckless, antisocial, or isolating behaviors is evident prior to the onset of suicidal behaviors, thus emphasizing that the recognition of these manifested behaviors is paramount to the identification of the adolescent at risk for suicide. Approaches to the identification, evaluation, and treatment of the suicidal adolescent are discussed. Prevention strategies are reviewed, emphasizing the relevance of identifying the underlying precipitant to suicidal behavior. Until a biologic marker for suicide is elucidated, the identification of high-risk groups, followed by a comprehensive evaluation for psychiatric disturbances, family disruptions, and psychosocial stressors and traumas, may be the most efficacious approach to preventing subsequent suicidal behaviors in adolescents.