OBJECTIVE: This study examined the rates and correlates of mental health care performance measures in the Health Employer Data and Information Set (HEDIS). METHOD: For all 384 health maintenance organizations (HMOs) participating in the HEDIS program of the National Committee for Quality Assurance during 1999, analyses examined the rates of compliance with five mental health care performance measures and their association with general medical care quality, public reporting, and HMO finances. RESULTS: The mean rate of mental health care performance was 48.0%, compared with 69.2% for non-mental-health care domains. In multivariate models adjusted for plan characteristics, scores for worse quality of non-mental-health domains, failure to report data publicly, and low medical-loss ratio (proportion of revenues spent on clinical care) all predicted poor mental health care performance. CONCLUSIONS: Better general medical care, transparency of reporting, and commitment of fiscal resources to clinical care predicted better mental health care performance for U.S. HMOs.