The 1928–1929 Great Barrier Reef Expedition marks an important milestone in the evolution of modern coral reef science, from its nineteenth-century theoretical and deductive foundation – so clearly exemplified in Darwin’s coral reef theory – to the twentieth-century focus on empirical and analytical studies. Here, we consider the anatomy of the expedition, its antecedents, its immediate scientific achievements and its longer-term legacy. This truly interdisciplinary expedition differed from its ship-borne or short-stay reef reconnaissance predecessors, being housed on a single reef and sand cay (Low Isles, northern Great Barrier Reef) for a period of 13 months. Its intensive, rather than extensive, investigations involved meticulous microscopic work and painstaking laboratory and field observation, measurement and experimentation, cataloguing linkages between reef habitats, tidal processes and physical and chemical properties of water, as well as a quantitative inventory of reef-flat and reef-front biota spatially grounded in accurate transect surveys and planimetric controls. Results were published in the Expedition’s exhaustive Scientific Reports over the next three decades, as well as in a host of other scientific journals.

We assess the Expedition’s major achievements: highlighting the importance of the carnivorous diet of corals; describing a natural coral bleaching event and mechanisms of algal loss; determining how corals survive submerged within variably oxygenated and turbid waters; estimating adult and juvenile coral growth rates and the effects of transplanting corals; understanding relationships between lunar periodicity and mass spawning of corals; and recognizing the commonalities and differences in reeftop sediments and landforms and their indicative role of past storms and sea levels and contemporary morpho-dynamic changes. Finally, we argue that these and many other topics explored during the expedition continue to be relevant in modern reef science, not least in providing an exceptional set of ecological and geomorphological benchmarks against which it has been possible both to measure one hundred years of ecological and morphological change and to provide a dynamical environmental envelope against which to assess potential future changes.