The Southern Ocean is a unique ecosystem with highly coveted marine resources. It includes the largest marine protected area anywhere, with management spread across national jurisdictions and a number of international bodies and cooperative arrangements. The area has local, national and international stakeholders with interests in an array of activities, such as fishing, tourism and scientific research. This article sheds light on the linkages between climate change and governance of Southern Ocean marine territories. It unravels the complexity of governing this marine region, in the process looking at biodiversity conservation, exploitation of resources and military activities. Using socio-historic analysis and ethnographic observation, it examines multiple decision-making areas, institutions, groups and actors. Issues examined in this artice include marine protected areas, fisheries management and environmental impacts of melting Antarctic ice and French subantarctic territories. These issues are viewed through the prisms of knowledge and policy – a knowledge-policy interface. Case studies highlight the interactions between human activities and climate change in Southern Ocean ecosystems. Real-world examples illustrate the governance of marine ecosystems and resources and demonstrate adaptations to environmental changes already affecting sub-Antarctic societies.