Australia has benefited immensely from the maritime zone provisions of the 1982 United Nations Convention on the Law of the Sea (LOSC), particularly the provisions for the Extended Continental Shelf under Article 76. Australia’s comprehensive submission of continental shelf data to the Commission on the Limits of the Continental Shelf in 2004 included data occurring inside the Antarctic Treaty Area for three separate Australian territories; the Australian Antarctic Territory, Heard Island and McDonald Islands, and Macquarie Island. This raises questions surrounding the interactions between the LOSC and the Antarctic Treaty in the Southern Ocean. The paper focuses on the Kerguelen Plateau continental shelf deliniation, offering a timely analysis of Australia’s strategic interests here, as Australia seeks to prepare a new or revised Extended Continental Shelf data submission for Williams Ridge. Australia has sought to strike a strategic balance between supporting its territorial interests and derived benefits under LOSC in the Southern Ocean, whilst maintaining and further enhancing some of the key values and norms of the Antarctic Treaty System (ATS). The Kergulen Plateau case represents a strategic pursuit of territorial interests, carefully balanced with a determination to strengthen Australia’s influence within the ATS and enhance the reach of its provisions, particularly in regard to environmental protection and the mining prohibition under the Madrid Protocol.