Despite the evidence that rates of mental health problems are high among adjudicated youth, especially females, there is a paucity of research longitudinally investigating gender differences in the mental health outcomes of this population once they reach adulthood. The current study examined longitudinal data from 405 adolescents who received an order from the Youth Court of Montreal, Canada between 1992 and 1993 in order to assess prevalence of suicide attempts and psychological help-seeking in this population. The study also probed gender differences in rates of reported mental health problems. Personal and social adaptation were assessed during structured interviews on three occasions. Data from the third wave of testing provided information on mental health outcomes in adulthood. Results of statistical analyses indicated that 20 percent of females and 10 percent of males reported suicide attempts and one-third of females and one-fifth of males reported psychology help-seeking. Similar proportions were discovered for reported psychiatric hospitalizations and/or participation in drug addiction programs. These findings suggest that adjudicated adolescents, especially females, are in need of more mental health interventions during their rehabilitation programming. Future research should attempt to identify subgroups of adolescent offenders with more serious mental health problems. Tables, references