What major problems are likely to be encountered in designing and implementing pay-for-performance mechanisms for public bureaucrats? This paper examines this question in the context of tax administration, drawing on both economic theory and recent reform efforts in developing countries. Incentive schemes may or may not increase corruption; more important is their effect on taxpayer compliance and government revenues. Whether incentive schemes enhance or reduce welfare depends on institutional parameters. These parameters include the precise range of instruments available for providing incentives, the extent of discretion available to bureaucrats, and the relevant dimensions of bureaucratic performance. Also pertinent are the importance of teamwork and equity within the bureaucracy, taxpayer appeal mechanisms, and the external legal and political environment. This implies the need to accompany incentive reforms with wider reforms in the internal organization of bureaucracies. Facilitating reforms in information systems, organizational structure, budgeting and accounting systems, task assignments, and staffing policies are described.