Quality of life is a major goal in the context of preventive and therapeutic cardiology. It is important, both as an outcome measure in clinical trials of congestive heart failure (CHF) and as a consideration in individual physicians' therapeutic decisions. In this article, quality of life concepts are reviewed, methods of measurement are explored and clinically significant changes on prognosis are discussed. There is a need for more research which is based on carefully selected measures of quality of life chosen as being of particular importance to patients and to the hypotheses being tested.