A focus on results is a central element in recent public sector reforms in OECD countries. Evaluation is important in a results oriented environment because it provides feedback on the efficiency, effectiveness and performance of public policies and can be critical to policy improvement and innovation. In essence, it contributes to accountable governance. The objective of evaluation is to improve decision-making at all levels. Yet its actual use has often proved to be limited, especially in relation to key policy decisions and budget reallocations. These guidelines identify key issues and practices that OECD Member countries should consider when seeking to improve the use of evaluations. They focus on management of evaluation activities in government and management of individual evaluations rather than on methodological questions. It is not their role to determine when evaluation is the most appropriate input to the policy making and performance management process. That decision will best be taken by the Member countries themselves.