The growing risks and impacts of climate change and the accompanying loss of ecosystem services require the world to urgently invest in a new development paradigm. As the UN’s global development network, UNDP recognizes the increasing urgency of mainstreaming climate change into sustainable development planning at all levels, linking development policies with the financing of solutions and helping countries move towards less carbon intensive economies. The Large Marine Ecosystem (LME) approach recommends a baseline of information at the LME management scale on changing states of productivity, fish and fisheries, pollution and ecosystem health, and socioeconomic and governance conditions. This information provides data to assess the extent of overfishing, nutrient over-enrichment, habitat loss, and warming in LMEs around the globe. Through the GEF’s Transboundary Diagnostic Analysis/Strategic Action Programme (TDA/SAP) approach, this LME data set can inform issue prioritization, strategic planning and adaptive management of LMEs towards sustainability. This volume is a key contribution to advancing LME management in a changing climate. The authors describe the impacts of climate change on LME sustainability in Africa, Asia, and Latin America and the key role the GEF has played in mobilizing financial support crucial to developing countries committed to carrying forward an ecosystem based approach to sustain LME goods and services.