While there have been efforts to assess the formal accountability systems of countries that will receive, generate, and manage substantial climate change funds — the UNDP’s Climate Public Expenditure and Institutional Reviews (CPEIR) stand out in this regard — there has been little work to date that assesses the full climate finance “accountability ecosystems,” including the roles, relationships between and among, and interactions of the range of state and nonstate actors. In response, the UNDP’s Governance of Climate Change Finance Team partnered with the International Budget Partnership (IBP) to assess the accountability ecosystems for climate change finance in four countries (Bangladesh, India, Nepal, and the Philippines) in the Asia-Pacific region, with an emphasis on CSOs and media. The aims of the assessment are to understand progress to date in establishing accountability systems for climate change finance, draw lessons, and guide actors — both global and domestic — on entry points to strengthen systems.