OBJECTIVE The authors' goal was to assess the effects of facility ownership on the characteristics of psychiatric inpatients treated in public, private nonprofit, or proprietary general hospitals. METHODS Data from the 1993 National Hospital Discharge Survey were analyzed to determine the number, sociodemographic and diagnostic composition, and treatment characteristics of patients with primary mental disorders discharged from public, private nonprofit, and proprietary general hospitals. RESULTS An estimated 1.83 million patients with a primary mental disorder diagnosis were discharged from general hospitals in 1993; the number of such discharges in the National Hospital Discharge Survey, which excluded federal general hospitals, was 13,086. These patients were unevenly distributed among public (9.4%), private nonprofit (78.9%), and proprietary (11.7%) hospitals. Psychiatric patients of public and private nonprofit hospitals were more likely to be diagnosed with schizophrenia (public: 23.4%, nonprofit: 18.8%, proprietary: 12.6%), a comorbid substance-related disorder (public: 29.9%, nonprofit: 31.0%, proprietary: 17.4%), a personality disorder (public: 11.6%, nonprofit: 11.3%, proprietary: 4.7%), or a general medical disorder (public: 62.4%, nonprofit: 57.4%, proprietary: 41.1%) than patients of proprietary hospitals. Uninsured psychiatric patients were far more common at public hospitals than at the other types of facilities (public: 17.0%, nonprofit: 9.9%, proprietary: 6.4%). CONCLUSIONS Public general hospitals play an important role in caring for uninsured patients with severe mental illness. Before widespread closures occur in the public general hospital sector, it is critical that policy makers identify and develop resources to replace the care these institutions currently provide to poor patients with severe psychiatric disorders.