This project aimed to develop multidisciplinary knowledge for a more sustainable and integrated coastal zone management by reflecting on existing forms of coastal governance and knowledge use. A review of coastal governance on different levels as well as a review of the usefulness of decision support system for coastal management has resulted in a list of conditions that have to be fulfilled in order to enhance the changes for a more successful integrated coastal zone management. This set of prerequisites was used to structure action research on the development of integrated coastal zone projects in Bulgaria. The project has also resulted in the development and testing of QUASTA, a computer-based tool that can be used in structuring societal debates by visualizing the relations between stakeholder ideas. The Quasta tool is among others tested in a project in which explorative scenarios for the future of Netherlands coastal zone were elaborated.