Quality of life assessment is increasingly acknowledged as an important component in selecting optimal health interventions for persons with cardiovascular disease. We hypothesized that cardiac out-patients have the same perception of what comprises quality of life as do their health care providers. A list of items was compiled from all quality of life measures and quality of life research. Staff members, cardiac out-patients and family members were asked what they considered important to the patients' quality of life by rating the relative importance of each item on the list. The three groups differed in their ratings. Of the top ten items ranked by patients, only three items appeared on the staff top ten list, and five on the family member's list. The patients, in contrast with staff and family, chose aspects of QL that reflected the positive aspects of life. These differences were more marked in the physical, psychological, and activity domains than in the social domain. The study suggests that QL measures developed from the perspective of primary caregivers are probably invalid and therefore QL measures should be developed from a patients perspective.