Relations between managers and professionals in the public sector have often centred on the control of work performance. Work performance strategies and techniques have been transformed by recent public sector policies involving managerialisation and quasi-markets. In particular, the clinical audit programme in the National Health Service has traditionally been the preserve of professionals, mainly doctors but managers and purchasers have become more involved recently. Based on an empirical study, this paper explores the ways in which Health Authorities were approaching their responsibilities, the consequences of such strategies for purchasers and providers, and the implications for professional-managerial relations. The paper concludes that purchasers have not made substantial progress in assessing work performance because of professional resistance and the non-threatening environment fostered by some purchasers.