The OECD’s work on subnational green budgeting was first developed within a joint project with the European Commission DG REGIO, titled "Measuring and Enhancing Subnational Government Finance for Environment and Climate Action in OECD and EU Countries”, launched in 2022.
More broadly, the Paris Collaborative on Green Budgeting, established in 2017 with the OECD serving as the Secretariat, seeks to design innovative tools for national and subnational governments to better align national expenditure and revenue processes with climate and environmental goals.