The synthesis report summarizes the findings of a multilevel analysis of synergies and complementarities between funding streams from different multilateral climate finance mechanisms, including the Green Climate Fund (GCF) and the Climate Investment Funds (CIFs), as well as interactions and synergies with the Global Environment Facility (GEF) and the Adaptation Fund (AF). It is based on four case studies, a portfolio analysis and additional stakeholder interviews. These describe mechanisms and situations where synergies between climate finance mechanisms and the initiatives they have funded arise. The synthesis report presents drivers of and challenges to such synergies and indicates areas for optimization. The case studies document different types of synergies in the renewable energy sector development in Kazakhstan, adaptation and resilience work in Cambodia and Namibia, and sustainable energy in Mongolia.