The study found that after controlling for demographic variables, delinquency was prospectively associated with an increased risk for suicidal thoughts, suicide attempts, and treatment for suicide attempts 1 year later. Seven years later, delinquency was associated with suicidal thoughts and suicide attempts, but not treatment for suicide attempts. After controlling for other risk factors (depression, low self-esteem, problem drinking, impulsivity, and religiosity), delinquency was still significantly related to an increased likelihood for suicidal thoughts 1 and 7 years later, and to suicide attempts 1 year later. Delinquency was significantly related to suicidal thoughts for girls more than for boys. The findings suggest that delinquent youth, particularly delinquent girls, should be targeted for interventions designed to reduce suicidal behaviors. Data from the National Longitudinal Study of Adolescent Health were used to assess the prospective associations between delinquency at ages 12-17 and suicidal behaviors that encompassed suicidal thoughts, suicide attempts, and treatment for suicide attempts 1 year and 7 years later. A total of 15,034 youth participated in the study. Fifteen items were used to measure delinquent behavior over the past 12 months. The analysis controlled for three person-level demographic variables (age, gender, and ethnicity) and the environmental variable of metropolitan status. The study also controlled for five other risk-factor variables shown to be related to suicidal behavior: alcohol problems, depression, low self-esteem, impulsivity, and religiosity. 1 table, 33 references