France is currently one of the leading shellfish production countries in Europe, harvesting more than 150,000 metric tons of the Pacific cupped oyster (Crassostrea gigas) and 60,000 tons of mussels (Mytilus edulis and M. galloprocincialis) each year. Among rearing areas, the Charentais Sounds and the Marennes-Oleron Bay rank first in Europe, with an annual production of 40,000 and 15,000 tons of oysters and mussels respectively. More than a third of French production is marketed from the Marennes-Oleron area. As natural C. gigas and M. edulis spatfall is limited to the Atlantic coast, the Marennes-Oleron Bay and the Charentais Sounds play a critical role nationally, representing more than half of French oyster and mussel spat production. The stocking biomass in this area was recently estimated at 125,000 and 20,000 tons of oysters and mussels respectively. This biomass is deployed over 4,000 ha of leasing grounds along the coastal area and 3,000 ha of wetlands (oyster ponds), which are environmentally sensitive and subject to numerous recent regulations. Although a traditional, century-old activity, the shellfish industry now has to address various new internal and external constraints affecting overall economic yield and sustainability. These include the management of freshwater inputs into the coastal area, impacted at the watershed level by agriculture from a qualitative and quantitative point of view (e.g. irrigation activity). Moreover, the Charentais Sounds need to remain competitive on the open market with other French and European production sites, whereas its biological yield remains one of the lowest in France. This has prompted the industry to optimize spatial distribution, restructure current leasing grounds and assess new management practices as well as new rearing techniques (offshore, long lines), which have led to conflicts over available space. In addition to technical constraints, local, national and European regulations have increased significantly. The coastal law, water law, bird directives, and regulations concerning the preservation of natural habitats, wild flora and fauna and protected areas are among the acts likely to have an impact on the shellfish industry in the near future. These internal and external constraints on aquaculture sustainability are analyzed, and certain case studies in the Charentais Sounds that have led to user conflicts are reviewed. The diversity of habitats, human activities and interests along this coast have resulted in highly complex situations in which some management attempts have been partly successful and others have failed. These management options are analyzed, and ongoing new approaches are described, including cooperative strategies among marine biologists, sociologists, economists, managers, coastal users, and the shellfish industry. Based on this analysis, requirements for the development of an integrated CZM plan in the Charentais Sounds are suggested, including the use of a proactive approach, geomatics and operational models, as well as the development of integrated decision making structure to develop CZM and then, the use of a stepwise model of agreement-focused negociation for further consensus building.