Rijkswaterstaat (RWS) is responsible for the design, construction, management and maintenance of the low-land river systems in the Netherlands. These systems need to reconcile a number of functions, such as protection against floods and provision of safe and efficient navigation, floodplain agriculture, ecology and recreation. Understanding fluvial processes and knowledge about the physical functioning of river systems is essential to make this possible, to design effective river engineering works, for operational forecasting and for maintenance of the river system. Therefore, RWS recognizes the importance of knowledge about the system behavior and strengthened his knowledge position by starting the Community of Practice (CoP) Lowland River Systems at the end of 2017. This CoP is responsible for developing, sharing and imbedding knowledge for river engineering and management practice in the Netherlands. Experts of both Rijkswaterstaat and knowledge institutes take part in the community.