Adolescent substance abuse is a major public health concern. It is associated with an increased incidence of various psychiatric disorders. The relationship between mental & behavioural disorders & substance use problems seems to be bidirectional. Adolescent suicide & substance abuse have a number of risk factors in common. Prevention of suicide requires an individualized comprehensive assessment & management plan aimed at substance use & psychiatric disorders. This would involve a multidisciplinary collaboration & the use of pharmacological, psychological, & social interventions. (38 refs.)