Concerns about both the cost and quality of health care have led to a growing interest in, and call for "pay for performance." Increasingly, as well, patient satisfaction is being viewed as an essential aspect of care that should be considered in judging performance. At the same time, there are concerns about the validity of patient satisfaction as a relevant quality measure. We argue that patient satisfaction is not only an outcome measure, but also an essential part of the process of care itself. This experiential aspect of care, however, is evaluated by patients, whereas formal processes and outcomes are recorded and evaluated by providers. As such, the 2 measures are evaluating different aspects of care that need not--but typically do--coincide. We also suggest that where patient satisfaction is utilized in pay for performance calculations, it constitutes a very small portion of the total money at stake and is unlikely to lead to "gaming" through acquiescence to patients' requests for unnecessary treatments.