Imagine 4 concentric circles representing all deficiencies in the quality of health care (Figure). At the center is the problem of patient safety, the most extreme violation of quality, in which the attempt to heal has the perverse effect of causing harm. The center blurs into the larger circle of medical errors, which connotes a larger category of mistakes that endanger patients in domains other than “safety,” such as mistakes that create deficiencies in managing chronic disease (9). That circle of errors, in turn, blurs into the larger circle of gaps in quality, encompassing not only individual errors but also the broader organizational causes of inadequate care, including restricted access to care (7), racial and ethnic disparities (8), systemic quality defects introduced by insurance and management policies, faulty information systems, and flawed system designs. This circle encompasses underuse, overuse, and misuse of care (10). Some envision a fourth circle: the extent to which the technical elements of care seem good on the basis of performance indicators but ultimately fail to be caring because of deficiencies not captured by these measures (11–12). The rudeness or insensitivity that patients encounter or the frustrations they experience in obtaining information and control over treatment decisions illustrate gaps in quality, of deep concern to the public (13), that often are not measured under normative standards.