Findings show that patterns of criminal behavior differed between depressed and nondepressed delinquent adolescents. Depressed adolescents engaged in a broader range of delinquent behavior than nondepressed adolescents, who typically specialized in one type of offense. Nondepressed delinquent boys most often specialized in violent offenses. Nondepressed delinquent girls tended to specialize in shoplifting. Although most depressed delinquent boys had committed a variety of offenses, those who did specialize tended to commit violent offenses. Among the depressed delinquent girls who specialized, vandalism was most often the type of offense committed. This study shows the importance of psychological assessments in framing and treating delinquent behavioral patterns. The study sample consisted of 3,679 adolescents, ages 14-16, living in Finland and who had repeatedly committed delinquent acts. They were participants in the Finnish School Health Promotion Study in April 2002. The self-report questions on delinquent behavior were adopted from the Finnish Self-Report Delinquency Study questionnaire, which is a modified version of the International Self-Report Delinquency Study. Differences in criminal activities between depressed and nondepressed delinquent adolescents were determined by comparing the frequencies of self-reported delinquency between the groups. Depression was assessed with a Finnish modification of the 13-item Beck Depression Inventory. 3 tables and 30 references