Despite having the most costly health system in the world, the United States consistently underperforms on most dimensions of performance, relative to other countries. This report—an update to three earlier editions—includes data from seven countries and incorporates patients' and physicians' survey results on care experiences and ratings on dimensions of care. Compared with six other nations—Australia, Canada, Germany, the Netherlands, New Zealand, and the United Kingdom—the U.S. health care system ranks last or next-to-last on five dimensions of a high performance health system: quality, access, efficiency, equity, and healthy lives. Newly enacted health reform legislation in the U.S. will start to address these problems by extending coverage to those without and helping to close gaps in coverage—leading to improved disease management, care coordination, and better outcomes over time.