The future is uncertain for the world’s large marine ecosystems. These relatively narrow ocean zones produce nearly 95% of useable marine biomass, yet are becoming increasingly stressed by both natural and anthropogenic changes. The potential for consequent negative effects on global ecologies and economies has aroused major international concern. This state-of-the-art update on Large Marine Ecosystems (LMEs) represents a multidisciplinary effort to develop a more holistic approach to the research, monitoring, and management of marine resources. The contributors deal with the various environmental and human impacts of ocean productivity, providing scientific, legal and technological arguments for managing LMEs as multinational units in order to sustain the biomass yields of major coastal areas.