The approach to the assessment and management of Large Marine Ecosystems (LMEs) has been the subject of a series of seminal symposia convened at the annual meetings of the American Association for the Advancement of Science. Since 1995, a five module approach to ecosystem-based management (EBM) of LMEs has been the focus of 110 economically developing countries around the globe engaged in 22 LMEs. A sum of $3.1 billion in financial assistance from the Global Environment Facility and the World Bank has been provided to support this global movement towards recovery and sustainability of LME goods and services in partnership with several OECD countries, five UN agencies, and two NGOs. LME stressors of prime concern are nutrient overenrichment and climate warming stress from projected levels of reduced primary productivity in LMEs located between 30°N and 30°S. Successful mitigation actions for reducing nutrient overenrichment in LMEs, and adaptive precautionary actions for protecting fish and fisheries in LMEs in the high-risk circumglobal belt are addressed. The paper concludes with comments on the unity of approach in the linking of science and policy in advancing toward sustainability of the world’s LMEs in accordance with Rio+20 goals.