We are demonstrating the tight connection between ending slavery and reducing environmental destruction. Our preliminary research shows that if slavery were a country, it would have a population of some 46 million people and the gross domestic product of Angola (in global terms a small and poor nation), yet would be the third largest emitter of CO2 (2.54 billion tons per year) in the world after China (7.39 billion tons) and the United States (5.58 billion tons). Responding to this, we are completing the world’s largest study on the relationship between slavery and ecosystems. This work will: Compile, synthesise and integrate spatial data on the landscape changes that result from slavery activities and calculate the environmental costs of these activities and the potential gains that stem from curtailing slavery, with a focus on carbon sequestration and other ecosystem services. Explore the values associated with environmental gains, their capacity to be captured in environmental markets, and their ability to help fund slavery prevention and abolition efforts. Explore links between ecological resilience and human vulnerability as a precondition to enslavement.