BACKGROUND: The delivery system for psychiatric inpatient services in the United States has changed dramatically over the past 30 years, undergoing a marked privatization. METHOD: To assess the effect of changes in ownership and types of inpatient settings on the structure of the mental health services system, the authors surveyed a national sample of nonfederal mental health facilities in 1988. RESULTS: Comparing their data to those of earlier surveys, they found that a decline in the number of patients per staff occurred in most settings over the last decade, suggesting that this aspect of quality of care may have improved. They observed important ownership-related differences in 1988 in diagnostic mix (e.g., more schizophrenia treated in public facilities than in private ones) and in payer source (e.g., more third-party revenues in public facilities than occurred in the past). CONCLUSIONS: There was a significant interaction between ownership form and type of facility, suggesting that the type of inpatient setting, ownership, and the relation between the two should be considered in assessing the impact of privatization on the accessibility of health care available for the mentally ill. The authors found that the increase in private psychiatric hospitals has widened the availability and choice of treatment facilities for those with private funding sources (especially children and adolescents) but has not had a similar effect in increasing sources of care for the seriously mentally ill dependent upon public financing.Abstract Teaser