The apparently unlimited demand for health care, finite supply of reso
urces, the internal social market and continuous technological advance
s have given rise to increasing concern about the performance of healt
h services. We examine an important measure of health care performance
- avoidable mortality. Studies extending the scope of avoidable morta
lity and other outcome indicators are discussed. Although avoidable mo
rtality is limited to providing a warning signal of possible health ca
re deficiencies and is not an appropriate measure for all types of int
ervention, it still provides us with one of the best guides to the per
formance of health services.