THE plate tectonics model1,2 has been successful in explaining the orogenic features of the ocean basins and continents associated with the dispersal of Pangaea in post-Triassic time. Dewey and Bird3 extended these concepts, suggesting that there is a unique relationship between orogenesis and plate-margin tectonism, and various authors have, accordingly, interpreted certain Precambrian and Palaeozoic orogenic zones or ‘mobile belts’ as plate sutures4–5. We argue here that plate-margin tectonism is only one of several possible conditions for the development of an orogenic belt. We suggest that the plate tectonic model of orogenesis needs to be extended and modified, and this suggestion is discussed for Gondwanide Australia. Recent attempts to impose a rift (aulacogene)6 or subduction7 model for orogenesis in central Australia are confounded by the observed geological and geophysical facts pertinent to this region.