Abstract: The ‘Afsluitdijk’ is the largest salt water barrier in Europe and was constructed for sea flood protection in the Netherlands. The dike body causes a sharp boundary between the Wadden Sea and the delta of the river IJssel. There is no brackish estuarine zone anymore and the natural habitat of estuarine species has therefore completely disappeared. Besides that, the Afsluitdijk blocks migration routes of various anadromous and catadromous fish species among which Atlantic salmon, sea trout, lamprey species, shad species, smelt, three spined stickle back and European eel. The discharge of the river IJssel is spilled through spill gates at low tide. The spillgates close at high tide, therefore there is only a net output of fresh water. Large numbers of migratory fish are attracted to the fresh water flow in the Wadden Sea, however there is no alternative migration route into lake IJsselmeer and the River IJssel available nearby. In 2013 the project ‘Fish Friendly Spill gate management Afsluitdijk’ was started by Rijkswaterstaat. The project consist of three phases: 1. Inventory of possible alternative forms of spill gate management which allow fish to enter the fresh water zone (2013); 2. Testing of a chosen preferred variant of alternative management (2014); and 3. The implementation of the preferred variant (2015). The presentation focusses on the project process, the possible forms of alternative spill gate management, the results of the testing fase and the recommendations for the implementation phase