Abstract
The coastal lagoons and their adjacent wetlands are a real geographical specificities of the Languedoc and Roussillon coasts. Today, their management is no longer only considered in terms of water quality or biodiversity protection, but also in terms of flood control, shoreline erosion and expected sea level rise. These issues raise questions about the function given to lagoons in a coastal territorial system strongly influenced by metropolisation, the residential and touristical economy. Their management mobilizes a plurality of actors with heterogeneous responsabilities and the mobilization of multiple management tools and governance mechanisms. The article analyses the territorial and institutional configurations that are being built to address all these issues