In the 21st century, the primary challenge for health care is chronic illness. To meet this challenge, we need to think anew about the role of the patient in health and health care. There have been widespread calls for patient-centered care, but this model of care does not question deeply enough the goals of health care, the nature of the clinical problem, and the definition of health itself. We must instead pursue patient-centered health, which is a health perceived and produced by patients. We should not only respect, but promote patient autonomy as an essential component of this health. Objective health measures cannot capture the burden of chronic illness, so we need to draw on the patient's perspective to help define the clinical problem. We require a new definition of health as the capacity for meaningful action. It is recognized that patients play a central role in chronic illness care, but the concept of health behavior retards innovation. We seek not just an activated patient, but an autonomous patient who sets and pursues her own vital goals. To fully enlist patients, we must bridge the gap between impersonal disease processes and personal processes. This requires understanding how the roots of patient autonomy lie in the biological autonomy that allows organisms to carve their biological niche. It is time for us to recognize the patient as the primary customer for health care and the primary producer of health. Patient agency is both the primary means and primary end of health care.