| The DAC Working Party on Aid Evaluation (WP-EV) has developed this glossary of key terms in evaluation and results-based management because of the need to clarify concepts and to reduce the terminological confusion frequently encountered in these areas. Evaluation is a field where development partners - often with widely differing linguistic backgrounds - work together and need to use a common vocabulary. Over the years, however, definitions evolved in such a way that they bristled with fake friends, ambivalence and ambiguity. It had become urgent to clarify and refine the language employed and to give it a harmonious, common basis. With this publication, the WP-EV hopes to facilitate and improve dialogue and understanding among all those who are involved in development activities and their evaluation, whether in partner countries, development agencies and banks, or non-governmental organizations. It should serve as a valuable reference guide in evaluation training and in practical development work. The selection of terms and their definitions in the attached glossary have been carefully discussed and analyzed and have benefited from advice and inputs, notably from DAC Members and the academic evaluation community. A WP-EV Task Force, chaired by theWorld Bank, led the overall project, in collaboration with the Secretariat. France took the lead on the French version, whilst the Inter-American Development Bank produced the Spanish translation. Denmark, the Netherlands, Norway, and UNDP provided financial support for the initial collection and review work, and Switzerland contributed financial support for producing this free distribution publication. The process has been guided by the highest considerations of clarity and conciseness and a spirit of collaboration and compromise in terms of the willingness of major development agencies and banks not to impose their specific vocabulary on others. Although terminology will continue to evolve alongside changing development practices and management instruments, this glossary is a “state of-the-art ”of key terms in use today. Niels dabelstein Chair of the Working Party on Aid Evaluation |