There are presently few instruments available for identifying the economic value of biodiversity conservation and Natura 2000 areas; all too often, these are still regarded merely as a cost item. Demonstrating the socio-economic value for the local and national economy can help increase public support for protecting Natura 2000 areas. At the request of the Royal Society for the Protection of Birds (RSPB) CE Delft has therefore investigated the socio-economic added value of three nature areas: Grevelingen, Het Zwin and Waterdunen. The main components are revenues from energy recovery, fisheries, recreation, water storage and security, CO2 abatement and employment. The potential for capturing this value was also investigated, with a view to identifying new funding sources for managing these areas.