This policy paper by Kelly Devers analyzes the trend toward quality improvement (QI) efforts in health care, concluding that while QI alone is no magic bullet, it generally has modest, positive effects. The paper, funded by the Robert Wood Johnson Foundation, reviews the evolution of QI initiatives, the current evidence about whether QI interventions work, QIs promise for the future, and how to help it find success in health care. The paper offers recommendations for enhancing QI, including by providing incentives for providers to prioritize quality; improving education, training, and technical assistance; investing in health IT; and promoting greater collaboration across organizations.