In the framework of the Mediterranean Action Plan's “Ecosystem Approach Initiative" (EcAp), the environmental assessment of Mediterranean marine and coastal ecosystems is to be completed by a socio-economic analysis highlighting relationships between human societies and natural systems. A Correspondence Group on Economic and Social Analysis (COR ESA Group) has been established to develop and coordinate the socio-economic assessment of water uses and coastal areas of the Mediterranean at the regional, sub-regional and national scales. Plan Bleu and the MAP Coordinating Unit are in charge of leading the Group and implementing the ESA action.