Chair of the trilateral committee consisting of Prof. Dr. Jouke van Dijk, Mette Guldberg, later replaced by Prof. Dr. Jesper Bartholdy (Denmark) and Prof. Dr. Karsten Reise (Germany) appointed by the Wadden Sea Board for developing a Trilateral Research Agenda for the Wadden Sea Region and its World Heritage Site by the trilateral scientific community which is presented to and approved in the Leeuwarden Declaration of the 13th Trilateral Governmental Wadden Sea Conference and Council Meeting. Leeuwarden, The Netherlands, 17-18 May 2018.