H ealth care, like electricity, is an instrumental good, a means to an end. 1 We don't want kilowatt hours; we want hot showers and cold beer. We don't want to trek to the physician's office, we want health. How markets are structured determines how people behave. Energy policies have begun to reward utility companies for keeping people warm at the least possible cost, for example, through home insulation programs. Similarly, payment reforms in health care have begun to move away from those that reward volume to alternative approaches intended to improve the value of care. Patient-centered medical homes (PCMHs) were an important step, as fee-for-service payment provided no direct support for many key functions of primary care. Accountable care organizations (ACOs) were another advance, as they encourage collaboration across providers to improve care and lower costs. As we approach the fifth anniversary of the passage of the Affordable Care Act, it is a good time to reflect on how we are doing in payment policy-and how we might do better.The commentary by Edwards and colleagues in this issue focuses on the need to restructure payment for primary care, with a particular focus on how this might be accomplished within ACOs. 2 Health plans usually support the PCMH model through additional fees to support non-visit aspects of primary care on top of fee-for-service payments that continue to reward face-to-face visits. The authors contrast the PCMH and ACO models in terms of organizational structure, payment models, scope of accountability, and hypothesized degree of integration of specialists and hospitals. They conclude by suggesting possible approaches to integrating the PCMH model in ACOs: health plans could include explicit payments to primary care providers in ACOs (as in the PCMH model) and the performance-based payment component of ACOs could be restructured to more strongly reward the achievement of primary care principles.The commentary is an excellent reminder that how health care is organized and paid for is important. Both the PCMH and ACO models have strengths and limitations. The PCMH model provides additional resources to practices enabling them to more easily expand access. The limitations, however, are substantial: the payment model focuses on adherence to a set of structural criteria that have a variable evidence base; the model continues to rely on fee for service and thus emphasizes visit-based care, and the model leaves unaddressed the challenge of how primary care relates to specialists or hospitals (thus current attention to the medical neighborhood). 3 At the same time, because of the strong consensus on the need to strengthen primary care in the US, medical home initiatives are proliferating-with a still limited evidence base on their effectiveness. 4 The ACO model includes a commitment to ensuring high-quality primary care. But it differs in several important ways. The ACO model was intentionally designed to encourage the emergence of organizations that could be responsible for the full contin...