<jats:p>Antarctica and its surrounding ocean host unique, endemic and cold adapted ecosystems. The Southern Ocean is furthermore, highly productive and provides globally important ecosystem services, from carbon sequestration to substantial genetic resources. The Antarctic region is a natural reserve for iconic marine mammals, penguins and flying seabirds, as well as krill and wider zooplankton communities that underpin pelagic food webs and biogeochemical cycling. Recent environmental changes such as rapid warming, ice loss, permafrost thawing, ocean acidification and arrival of pathogens and pollutants pose risks and uncertainties to Antarctic life as we know it. Furthermore, Antarctica and the Southern Ocean still host the least studied regions, and the largest gaps in biodiversity knowledge. This theme thus aims to strengthen the scientific basis for understanding and protecting Antarctic life across environmental boundaries, from terrestrial and intertidal habitats and ice shelves, surface waters down to the seafloor, and from microbes to top predators. It will integrate novel approaches for rapid biodiversity discovery and functional analyses of the networks of life in the Antarctic region. By integrating observations of terrestrial, sea-ice, pelagic and benthic biota and habitats, standardising protocols, and building cross-national collaborations, Antarctica InSync will enable a more holistic circum-Antarctic view of ecosystem dynamics and resilience in a rapidly changing environment. However, delivering representative circumpolar observations will depend on coordinated governance and operations across national programmes, including logistics, permitting pathways, standardised QA/QC procedures and harmonised data stewardship.</jats:p>