This document describes how the OECD DAC Network on Development Evaluation (EvalNet) revisited the definitions and use of the OECD DAC evaluation criteria in 2018-2019. The document lays out adapted definitions for relevance, effectiveness, efficiency, impact and sustainability, and for one new criterion, coherence. The document describes how the criteria should be used thoughtfully, and adjusted to the context of the intervention and the intended users’ needs. These revised definitions and principles for use are the result of a global consultation on the criteria and a review of how they are used in evaluation and beyond. Following the consultation, members of EvalNet and outside evaluation experts discussed the concepts in depth and reviewed several drafts. The adapted definitions are clearer and will support more rigorous, nuanced analysis, including of equity issues and synergies, in line with current policy priorities. This adaptation also addresses confusion, by adding an introduction on the intended purpose of the criteria and guiding principles for use. Detailed guidance on the application of the criteria is to be provided separately, after adoption.