This collaborative project between the Australian Antarctic Division (AAD) and the Institute for Marine and Antarctic Studies (IMAS) addressed key research needs between 2018 and 2020 for Patagonian Toothfish (Dissostichus eleginoides), Antarctic Toothfish (Dissostichus mawsoni) and Mackerel Icefish (Champsocephalus gunnari) which are targeted by Australian fishing vessels at Heard Island and McDonald Islands (HIMI), Macquarie Island (MI) and in exploratory fisheries managed by the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) in the Australian Antarctic Territory (AAT) and the Ross and Amundsen Seas. The project substantially advanced our understanding of the population dynamics of Toothfish and Icefish, in particular it provided robust estimates of key population parameters, and updated and improved the stock assessments for these species at HIMI. Significant work was also conducted to evaluate seabird interactions in the HIMI Toothfish longline fishery, assess skate bycatch at HIMI, and advance research towards the development of an integrated stock assessment for Toothfish in the AAT.