The Blue Flag programme, established by the Foundation for Environmental Education (FEE) in 1987, has made substantial contributions to Ocean Literacy over its 35-year history, by promoting environmental education, sustainable tourism, and marine conservation. The Blue Flag programme has influenced policies, engaged communities, and enhanced public awareness of marine ecosystems on a global scale. This chapter explains FEE’s vision to advance sustainable development through education, detailing its international network, and Blue Flag Programme’s pivotal role in fostering Ocean Literacy through education, public engagement, and policy influence. It also shows how FEE’s initiatives, such as the Global Action Days Campaign and the GAIA 20:30 Strategy, are closely aligned with the United Nations Decade of Ocean Science for Sustainable Development (2021–2030) as well as with the United Nations Decade on Ecosystem Restoration (2021–2030), contributing to scientific research, marine conservation, pollution reduction, and climate resilience, while strengthening global cooperation for sustainable Ocean management. The GAIA 20:30 Strategy supports international sustainability goals by emphasising climate action, biodiversity protection, and sustainable livelihoods. Through citizen science, advocacy, and partnerships, these efforts drive Ocean Literacy and promote responsible marine stewardship, underscoring the importance of integrating education, research, and policy to ensure Ocean sustainability now and in the future through both Decades. As environmental challenges intensify, the continued expansion of FEE’s initiatives will be critical in cultivating a global culture of Ocean Conservation and ensuring the long-term health of marine ecosystems.