Stuart Bunn is internationally recognised for his research on the structure and function of freshwater ecosystems. His work challenges established wisdom about aquatic food webs, establishing a new understanding that emphasises the key role of high-quality algae as a basal resource, and the connectivity of energy and nutrient flows across rivers, floodplains and estuaries, along with terrestrial inputs. Bunn has played key roles in building Australia’s national research capacity in freshwater ecology, forging international connections and visibility, and translating his deep knowledge of ecosystem function to guide management of flow regimes of freshwater systems in Australia and internationally.