A valid measure of practice systems for improving chronic disease care is needed as a guide for both improvement and public accountability. We tested whether a new survey measure of the presence of practice systems (the PPC-R) is associated with performance measure rates for depression among 40 medical groups in Minnesota. These PPC-R scores were compared with standardized medical group measures of antidepressant persistence. Only 54% of potentially important systems were present, and there was high variability. However, there was a positive correlation between systems and quality on the 90-day measure of antidepressant persistence, both overall (r = .33, P = .04) and for the Chronic Care Model domains of decision support (r = .38, P = .02) and delivery system redesign (r = .31, P = .05). Thus, practice systems overall and several domains of the Chronic Care Model appear to be associated with higher quality care for depression. This questionnaire may help practices identify particular systems to improve.