Both suicidal ideation and actual suicide attempts were far more common among the girls than among the boys. The data indicate that the relationship between drug use and depressive mood was much stronger for females than for males, but some of the within-sex differences were not statistically significant. Suicidal youths were ill-adjusted and displayed a lack of attachments and commitment to family and school. Causal models indicate that poor interpersonal interactions with parents, absence of peer interactions, and life events led to depression which in turn led to suicidal ideation. Depressive symptoms were the strongest predictors of suicidal ideation. Among females, depression predicted drug involvement, and, in turn, drug use increased suicidal ideation. Delinquency and eating disorders had direct effects on suicidal ideation beyond those of depressive affect. Understanding the dynamics of suicidal ideation in adolescence has important public health implications, since suicide ideation is a strong predictor of attempts, especially among females, 2 figures, 8 tables, and 39 references. (Author abstract modified)