In 2023, the Green Climate Fund (GCF) Independent Evaluation Unit (IEU) studied GCF activities in 12 developing countries as part of the Second Performance Review (SPR) of the GCF, which focused on the first replenishment period covering 2020–2023. These case studies explore countries’ efforts to lower greenhouse gas emissions and promote climate-resilient development in partnership with the GCF. This report summarizes key insights from those case studies, using data collected from March to August 2022.