A major issue facing the mental health and juvenile justice long-term care systems is the task of differentiating clinical characteristics and long-term residential treatment needs of the mentally ill population within community mental health systems from the mentally ill population of the juvenile justice systems. This study summarizes a body of literature on delinquent adolescents of the juvenile justice system and on non-delinquent adolescents of the mental health treatment system, including a database of risk and protective factors, and proposes a promising integrative, community-based treatment program. There remains an over representation of mental health disorders in delinquent adolescent populations. There is evidence that compared to their non-delinquent peers, incarcerated adolescents display high rates of attention deficit hyperactivity disorder, affective disorders, and substance use problems. The focus on levels of aggression and their mediating impact on delinquent adolescents with mental illness is important as an indicator of future violence and involvement in the justice system. The study indicates that the juvenile justice system is not designed to provide mental health services for large numbers of adolescents with mental health disorders. Research is needed to assist mental health and juvenile justice administrators to better understand and differentiate the overlapping interplay with theirs and other systems that claim to treat adolescents. Future longitudinal studies should be examined to determine if there are critical clinical characteristics that would improve the ability of researchers and clinicians to determine the most appropriate treatment setting for adolescents. tables, figures, references