Data on the psychiatric diagnosis, overall functioning, and treatment of 220 6- to 23-year-old subjects who were at high or low risk for major depression are presented. The subjects' diagnoses were made by a child psychiatrist based on best-estimate evaluation of diagnostic information derived from structured interviews (Schedule for Affective Disorders and Schizophrenia for School-Aged Children, Epidemiologic Version) with the subjects and separately with their mothers about their children. The major findings were an increased overall prevalence of major depression and substance abuse, psychiatric treatment, poor social functioning, and school problems in the children of depressed proband parents compared with children of normal proband parents. Overall prepubertal depression was uncommon and the sex ratios were equal. After 12 years of age, there was an increasing preponderance of female subjects in the group with major depression. The mean age at onset of major depression was similar for male and female subjects. However, it was significantly earlier in the children of depressed probands (mean age at onset, 12 to 13 years) compared with the children of normal probands (mean age at onset, 16 to 17 years). Symptom profiles and additional types of diagnoses in the depressed children from either proband parent group did not differ. These children are being followed up longitudinally to determine the prognostic significance, persistence, recurrence, and recall of their symptoms. Several research and clinical strategies are suggested by these data.