How was modern fishing methods, in the form of steam trawling, introduced in Australia? And what were the consequences for the fish stocks found on the South-East Continental Shelf? Through historical catch records and archival resources, the history of the NSW Steam Trawl Industry from 1915 to 1961 is unfolded. This reveals that government initiatives played a surprisingly decisive role in founding and sustaining the industry. Also that early signs of depletion of stocks and overfishing happened within the first decade of the fishery and, in the case of flathead, overfishing was so severe that flathead biomass on the South-East Continental shelf was permanently reduced. The study furthermore reveals how the trawl industry was influenced by government policy, market conditions, war and fishing effort with little understanding of the marine resources which they relied on.