The ICLEI Action Fund is a granting scheme conducted by ICLEI Local Governments for Sustainability with support from Google.org to foster data-driven environmental and climate action at the local level. The Fund foster activities that use climate data and contribute to cities’ just transition and climate plan with the aim to help cities reduce emissions and build resilience to climate change. Launched in May 2020 in Europe, the programme has granted 2,5 million EUR to six non-profit and academic organisations to implement projects aimed at reducing existing and avoiding new emissions of greenhouse gases. After a thorough round of evaluation, a team of sustainability experts selected for funding projects in Copenhagen (Denmark), Berlin and Hamburg (Germany), Birmingham and Oldham (UK), and Nantes (France) implementing action in sustainable mobility, energy-efficiency, air quality, and solar potential. The funded projects have used data to analyse and develop better ways to reduce air pollution, improve citizens’ lifestyle and health, evaluate buildings solar potential and energy-efficiency options, assess sustainable mobility measures implemented in the cities, study specific areas to create urban testbeds and more. With the results and impacts of each project, local governments have additional base and data to implement action towards emissions reduction and against climate change. Through the Action Fund, some of the selected local governments are participating in meetings, workshops and other events, hearing directly from the community what are their main needs; in other cities, the local administrations have engaged more closely with the project (Nantes, France) supporting the collection and analysis of the data, for example.