To obtain an optimal nature management and a sustainable economic use of (parts of) the coastal ecosystem - defined as the area between the lowest low waterline and the transition zone between dunes and polders - a multidisciplinary ecosystem concept is set up. This study deals with the biological aspects of this concept. An overview is made of the available biological data, a vegetation typology and vegetation map is made after which nature development goals are formulated. The last part contains specific proposals for the actual management measures to be taken.