Few, if any, areas of endeavor show a more complicated, and more consequential, tangle of publicness and privateness than health care. It is a prominent, but for the most part, poorly performing arena of public–private interaction in the United States. The governance of this vital sector of the economy – more than one-sixth of GDP – is collaborative; public funds pay for roughly half of medical services (with most of the private spending subsidized through tax preferences), while the vast majority of providers are private. America’s public leaders often fail to recognize the dynamic of shared discretion at the heart of the health-care system, and this failure contributes to the private sector delivering care that is less effective, affordable, and accessible than it should be.