This brief draws on recent reports by the OECD, the World Bank, the Overseas Development Institute (ODI), the Climate Policy Initiative (CPI) and others to provide an overview of climate finance in developing countries. The brief is divided into three sections: (i) sources of global climate finance; (ii) country-level flows of climate finance; and (iii) applications of climate finance in developing countries. The brief is designed to give a concise overview of financial flows directed at climate change mitigation and adaptation globally and in developing countries, with an introduction to climate finance accounting such that climate financial flow volumes can be compared to aid volumes in other sectors. Total global climate finance flows were approximately USD $364 billion in 2011 (Buchner et al., 2012) and $359 billion in 2012. However the vast majority of these flows - 76%, or $275 billion - was finance generated and spent within a country’s own borders (domestic finance) (Buchner et al., 2013). The “Fast-Start Finance” period from 2010-2012 saw $35 billion in new aid mobilized for climate finance in developing countries. Developed countries have recently committed to mobilize an additional $100 billion per year by 2020.