There are significant practical and jurisdictional challenges to the implementation and enforcement of international agreements. New Zealand is highly involved with Antarctic maritime regulation in three key capacities, as a Flag State, as a gateway Port State and as a claimant Coastal State. These three capacities come with varying jurisdictions and enforcement capacities, each with different challenges for exercising these powers. A further regulatory step taken by New Zealand in respect of its Antarctic claim is the proposed Ross Sea Marine Protected Area which comes with its own regulatory and enforcement challenges. With its Flag State enforcement powers limited by its small Antarctic fleet, there is an increased need to develop effective enforcement mechanisms and means to ensure that other States live up to their own Flag State responsibilities as regards Law of the Sea, Antarctic Treaty System and Marine Protected Areas.