The Global Environment Facility (GEF) Evaluation Policy (2019) requires that the lead GEF Agency will evaluate a program at the end of its implementation to provide a comprehensive and systematic account of its performance and the factors that affect performance. Program evaluations are expected to support accountability, learning, transparency, knowledge sharing, and decision making in the GEF. The purpose of these guidelines is to support GEF Agencies in conducting program evaluation, and to facilitate consistency and completeness in their reporting. These guidelines provide an update to the guidance issued in 2022. The update incorporates coherence as a separate evaluation criterion and harmonizes the rating scale used to assess sustainability. The guidelines are effective January 1, 2024.