Coastal lagoons are notoriously delicate and difficult to manage. In this collection of eight articles and four extensive case studies, contributors examine advanced methods of managing lagoons, including modeling and assessment. Their topics include identifying the ecosystem, analyzing physical and biogeochemical processes, gauging the effects of changing environmental conditions, applying modeling concepts, designing monitoring programs, and making decisions for sustainable use and development. Case studies include examples of wind-driven currents, fast-changing ecosystems under human pressure, transboundary management, and sustainable use and development.