The United Nations Evaluation Group (UNEG), as a group of professional practitioners, undertook to define norms and standards that aim at contributing to the professionalization of the evaluation function and at providing guidance to evaluation offices in preparing their evaluation policies or other aspects of their operations. This initiative was undertaken in part in response to General Assembly resolution A/RES/59/2501 of December 2004, which encouraged UNEG to make further progress in a system-wide collaboration on evaluation, in particular the harmonization and simplification of methodologies, norms, standards and cycles of evaluation.