Fossil fuels account for over three-fourths of greenhouse gas emissions, fuelling a climate crisis that is projected to devastate ecosystems and communities across the globe. The Fossil Fuel Atlas is a GIS-based open-access tool that shows the overlap between fossil fuel planned and existing fossil fuel production. This report gives an overview of the tool’s functions, the threats fossil fuels pose to biodiversity and ecosystems, and case studies that demonstrate the Fossil Fuel Atlas’s uses.