In the twenty-third episode of Ao Mar! - the official podcast of the Brazilian Institute for the Law of the Sea (BILOS) - we interviewed Andrei Polejack about Ocean Science Diplomacy, its creation and evolution, its importance for the Law of the Sea and for the achievement of sustainability in the context of the UN Decade of Ocean Science for Sustainable Development, and the impacts of using science for decision-making and ocean governance, in addition to the main challenges related to the theme.