How much time and money should we devote to quality activities? Will the results be worth the resources which we invest? How can we calculate the return on our quality investments? These questions are raised by managers, clinicians and policy-makers, but they are rarely answered, which may explain the loss of credibility of some quality activities. This paper gives examples of the cost of poor quality, describes and illustrates a simple method for quality costing, and discusses the economics of quality. It considers why there is little research and teaching about the subject, and proposes how managers and clinicians can take a more economically-informed approach to quality in public healthcare.