Objective:Behavioral health homes provide primary care health services to patients with serious mental illness treated in community mental health settings. The objective of this study was to compare quality and outcomes of care between an integrated behavioral health home and usual care.Method:The study was a randomized trial of a behavioral health home developed as a partnership between a community mental health center and a Federally Qualified Health Center. A total of 447 patients with a serious mental illness and one or more cardiometabolic risk factors were randomly assigned to either the behavioral health home or usual care for 12 months. Participants in the behavioral health home received integrated medical care on-site from a nurse practitioner and a full-time nurse care manager subcontracted through the health center.Results:Compared with usual care, the behavioral health home was associated with significant improvements in quality of cardiometabolic care, concordance of treatment with the chronic care model, and use of preventive services. For most cardiometabolic and general medical outcomes, both groups demonstrated improvement, although there were no statistically significant differences between the two groups over time.Conclusions:The results suggest that it is possible, even under challenging real-world conditions, to improve quality of care for patients with serious mental illness and cardiovascular risk factors. Improving quality of medical care may be necessary, but not sufficient, to improve the full range of medical outcomes in this vulnerable population.