Introduction Quality of life is generally acknowledged as a central concept in health care, but its full application in healthcare research and clinical practice are still being debated. With an increasing prevalence of chronic diseases and the focus of health care expanding from “adding years to life” to “adding life to years”, there is a growing interest in assessments of quality of life in health care. Measures of quality of life have been used almost exclusively in health services research to assess outcomes of care—that is, eVectiveness of care. Arguments in favour of this “outcome approach” are based upon the growth of the healthcare system, the need for cost containment, and the ensuing call for evidence-based health care. Less attention has been given to the use of quality of life for monitoring health needs as an index of the relative appropriateness of health care. Although the “outcome approach” is already widely established, the “need approach” has only recently gained attention. Chronically ill patients are particularly likely to benefit from need assessment and the routine use of patient derived data in making decisions about the distribution, access, and content of long term care. Comprehensive evaluations of health care must involve assessments of outcomes and needs. It is only by including both these assessments that the process of care for patients with a chronic disease can be improved. This article aims to clarify the interrelation between quality of life and quality of care. To elucidate this association we will use examples from our research on patients with stroke. The objectives are (a) to describe the necessity and use of measures of quality of life in health services research; (b) to examine the use of measures of quality of life to study outcomes of care and to illustrate how these measures can be used to assess the need for care; and (c) to discuss problems in quality assurance that are related to the comprehensiveness of chronic care.