These youths include those suffering from neurotic disorders or emotional disturbances specific to childhood and adolescence, those with severe psychopathology, those with conduct disorders and learning disorders, drug abusers, and those who are resistant to usual interventions. No single assessment instrument or approach is totally satisfactory for assessing these youths. However, assessments can focus on competence to stand trial, dangerousness, treatment planning and dispositions, psychometric classification, and psychological evaluation. Community-based treatment programs include individual and family therapies, diversion programs, programs emphasizing behavior modification, and outpatient programs attached to hospitals with psychiatric units. Residential treatment and therapeutic camping programs are also available. The service delivery system should include a range of alternatives, with the choice of setting and treatment techniques based on the nature and severity of the disorder and the youth's needs. 115 references