This review, which was undertaken primarily as a scoping exercise, seeks to clarify the evolving context for international support for large hydropower in developing countries, and the links to international carbon financing as a perceived route to climate change mitigation, including carbon trading systems. It aims to synthesise information on the relative coherence of the different safeguards, approaches and standards applied to large hydropower projects to enhance social and environmental performance, and sustainable outcomes more broadly. The report focuses mainly on large hydropower, identifying the roles of the voluntary guidelines and mandatory standards that stem from national legislation, river basin agreements, funding conditionalities and best practice. It also discusses the role of the private sector, the Equator Principle banks and the International Finance Corporation (IFC) and the increasing role played by China both domestically and internationally.