Two failings of U.S. health care have defined recent reform efforts: the escalating cost of health care—estimated to have reached $2.5 trillion in 2009 —and the swelling ranks of uninsured and underinsured Americans, now totaling some seventy-five million people. They share company with a third, however, that has attracted little attention. Tens of millions of poor and minority Americans experience levels of health typical of middle- or low-income countries. Differences in health status by social class, race and ethnicity, and geographic region are large and persistent in the United States. Guaranteed access to timely and quality primary care could improve our nation’s health, but no amount of health care can remedy social disparities in health. Health reform that makes health equity a goal demands a bolder agenda that acts on the social, economic, environmental, and political factors—or “social determinant of health”—implicated in the disproportionate incidence of disease and premature mortality among poor and minority groups.