Managed behavioral health care approaches have significantly reduced inpatient utilization and related cost of care, but the relationship between decreased utilization and cost of care to changes in quality of care performance over time remains in question. The trends in utilization and quality of care performance measures over the course of 10 years of the Tufts Health Plan Designated Facility Program, a model health maintenance organization capitated program for inpatient behavioral health care, are presented. The results indicate that substantial decreases in inpatient utilization were sustained while quality of care measures improved over time. The data support the Tufts Health Plan Designated Facility Program as a successful means of balancing cost containment with quality of care.