The level of functioning, treatment needs, and expected degree of compliance of 327 young adult patients who had a major psychiatric or substance abuse disorder were assessed retrospectively by the clinicians who provided their primary care in Missouri's public mental health system in 1982. Forty-eight percent of the patients were rated as having poor to grossly impaired functioning. Outpatient counseling, alcohol and drug abuse treatment, and outpatient crisis intervention were the most frequently named treatment needs. The most impaired patients were thought to be in greatest need of medication and crisis intervention, but to be most likely to comply with recommendations for outpatient counseling and psychotherapy. The authors believe that clinicians' assessments of needs of young adult psychiatric patients can serve as the basis of a model systern of care.