In the past ten years, Dr. Runnegar has provided a new understanding of the evolution of the Mollusca through his work on Palaeozoic fossils. He has developed a coherent new hypothesis explaining the origin of the major living and extinct classes of molluscs, has demonstrated that at least five major lineages of molluscs have much longer histories than previously suspected, and that early (Cambrian) molluscs may be used successfully for biostratigraphic and biogeographic purposes. His work on Permian geology has greatly clarified knowledge of the palaeontology, stratigraphy and structure of that system in Australia. He has made significant contributions to palaeontology in its evolutionary, biostratigraphic and palaeoecological aspects.