The co-ordinated and integrated approach of HYDRALAB aims at structuring the access to unique and costly hydraulic and ice engineering research infrastructures in the European Research Area. The network of HYDRALAB is unique in the hydraulic research community and has large experience in co-operating since its start in 1997. It began by informing and co-ordinating the activities of the partners in HYDRALAB I and II, and via strong collaboration in HYDRALAB III we will now realize further integration of our research services in Europe in HYDRALAB IV. Over the course of 10 years our network has grown from 8 participants in 1997 to a total of 30 participants from 15 countries today.Research in our infrastructures deals with complex questions regarding the interaction of water with environmental elements, sediment, structures and ice and goes beyond just hydraulic research: hence we have adopted the theme More than water. Questions that we need to answer deal with e.g. the development of adaptive strategies to climate change and sustainable measures against natural hazards, like floods.A fully integrated and balanced ensemble of Networking Activities (5), Joint Research Activities (4) and Transnational Access Activities (10) enhances the operation of our infrastructures and their instrumentation facilities beyond the present state-of-the-art and identifies potential future developments. By means of the common User Selection Procedure optimal access is guaranteed. With our dissemination events we foster a culture of co-operation between the participants and the wider user community.Further objectives of HYDRALAB IV are to improve access to experimental data, by providing researchers with a database on results of experiments, and bring young researchers and first time users from across Europe to the cutting edge of experimental research.As compared to the first proposal for HYDRALAB IV this proposal is improved with the recommendations made by the review panel.