Growth in Medicare expenditures has forced legislators and policymakers to look for ways to slow spending and get more value for their money. This article reviews previous federal efforts to control Medicare costs as well as current ones required by the Patient Protection and Affordable Care Act. It also describes a proposal for value-based purchasing that the authors developed under contract to the Centers for Medicare and Medicaid Services. This approach uses two measurement systems-one for physicians who practice primarily in outpatient settings and one for physicians who practice primarily in the hospital.