An evaluation is an assessment, as systematic and objective as possible, of an on-going or completed development intervention. The aim is to determine the relevance of the development objectives, developmental efficiency, effectiveness, impact and sustainability. An evaluation should provide information that is credible and useful, enabling the incorporation of lessons learned into the decision making process of both the partner and donor. At the Inter-American Development Bank, evaluation is used as a key tool for institutional learning and as an instrument for systematic assessment of the effectiveness of Bank development policies, the results of Bank-financed activities, and related processes.