Depression affects at least 2% of children under 12 years of age and 5% of teenagers. The syndrome of depression is a pervasive mood disorder associated with significant suffering or impairment of functioning. Mood is characteristically very variable and less pervasive than in adults. Trials of cognitive-behavioural therapy and interpersonal therapy, both in adolescents, have shown benefit, but these treatments may not be available in primary care or even in local clinics. In practice, sympathetic listening may be enough to help recovery, particularly if it is combined with attention to social factors and practical problem-solving. The first choice for the drug treatment of depression should now be selective serotonin reuptake inhibitors, because they are safer in overdose, and depressed adolescents are at high risk of impulsive overdose. An interesting clinical observation is that low doses of tricyclic antidepressants can be effective, perhaps because of the beneficial effects on sleep and anxiety, but this has not been confirmed by research.