This Climate Change Public Expenditure and Institutional Review Sourcebook (CCPEIR) seeks to provide practitioners with the tools and information needed to respond to the public expenditure policy and management challenges arising from climate change. It is a series of notes and supporting materials written as a first step towards consolidating current research and international experience, identifying emerging practice and providing practical and applicable guidance for staff of central finance agencies, development agencies, environmental agencies and other international organizations working on climate change issues. In addition to emphasizing the importance of strengthening national systems throughout, the Sourcebook focuses on the specific public expenditure policy and management challenges posed by climate change, such as decision-making in the face of uncertain future climate conditions, expenditure planning for extreme weather and climate events, the lack of agreed budget definition and classification of climate change activities.