There has been substantial interest in recent years, among research workers and in health service management, in the potential use of quality-adjusted life years (QALYs) as an aid to decision-making about the development of services and use of resources in health services (Gudex, 1986; Drummond, 1986). In 1986 the North Western Regional Health Authority (RHA) initiated the first large-scale attempt to use QALYs as a practical aid to planning in the National Health Service. This paper draws on the experience of the North Western RHA in examining some methodological and practical issues relating to the future of QALYs as an aid to decision-making in the Health Service.