There is a pressing need to establish robust baselines to monitor and predict the effects of anthropogenic activities and pollution on our ecosystems, including the impacts of climate change. This will inform best-practice management and help local populations to adapt to environmental changes. However, there is still a great deal to learn about South Atlantic ecosystems, across marine, freshwater and terrestrial habitats. Science undertaken through our Ecosystems focal area will leverage our expertise in fish ecology, seabird movement ecology, peatlands, wetlands and blue carbon to name but a few, to establish biodiversity and ecosystem baselines, that will enable South Atlantic environmental stewardship and sustainability. Our Ecosystems science will improve evidence-based management and conservation initiatives, will facilitate ecosystem-based management and increase the amount and quality of information available to researchers and decision makers.