Multi-institution quality improvement collaboratives have been used to successfully address a variety of patient safety problems, including medication errors and health care–associated infections. This controlled study, conducted in primary care clinics, examined the effect of a quality improvement collaborative designed to promote patient-centered care and enhance service quality. Clinics that participated in the collaborative did not achieve greater improvements in the targeted measures compared with control clinics, although all clinics (both intervention and control) showed improvement over the study period. The authors speculate that the collaborative approach may be useful for more specific, targeted safety problems.