With aquaculture production increasing rapidly in South Australia, as well as several other states including Tasmania, there is an increasing level of concern about the trade-offs between economic returns and environmental sustainability. In Australia, most aquaculture, particularly in-sea aquaculture, is undertaken on a single species basis. For finfish, which are fed a diet based on either baitfish or pelleted feeds, this means that a considerable amount of nutrients are released into the environment. For example, for the two main species farmed in Spencer Gulf in South Australia, southern bluefin tuna and yellowtail kingfish, for every tonne of production, as much as 500 and 200 kg respectively of nitrogen is released into the environment. In areas of high production, these wastes have the potential to stimulate plankton blooms and/or smother the benthos. As a consequence, stocking levels are closely regulated to reduce the potential for environmental harm, and there is considerable interest in methods for removing wastes and/or mitigating their impacts. IMTA thus has the potential to be utilised in Australia to both decrease the environmental impacts of finfish farming, and increase financial returns to the aquaculture industry. If successful, IMTA could be used to reduce nutrient inputs from farming into the marine environment, giving industry the flexibility to maintain higher stocking levels, leading to more optimal use of resources. Before IMTA can be undertaken on a commercial scale in the warm temperate waters of southern Australia, however, there are a number of questions that need to be addressed. These include what species and farming systems are suitable, what is the potential for the species used to act as an intermediate host for parasites of other species in the system, and are their any food safety issues that need to be addressed.