DANUBIUS-IP is a 39-month Coordination and Support Action to support the ongoing development of DANUBIUS-RI – an environmental research infrastructure linking rivers and seas – as it proceeds towards its Operational Phase. The project proposes 7 work packages, in two parallel workstreams, that together will: • deliver a new governance structure for the RI as it transitions to DANUBIUS-ERIC; • enhance the ICT potential of the RI to enable virtual delivery of key services; • implement the Science and Innovation Agenda supported by agile and quality assured scientific services; • demonstrate the value of the RI through examples of the unique services that the RI can offer to end-users across Europe and internationally; • expand the DANUBIUS-RI community and enhance its standing in the wider European and International environmental RI landscape; and • ensure that the potential of DANUBIUS-RI to have significant social and economic impact is widely communicated. DANUBIUS-IP is coordinated by GeoEcoMar (Romania) and brings together 25 experienced partners from 14 countries from across Europe in a consortium with complimentary areas of multi-disciplinary expertise across the freshwater and marine research fields. The project specifically seeks to address recommendations from the recent ESFRI and High-Level Expert Group reports (on DANUBIUS-RI) and make a significant contribution to the expected outcomes and wider impacts of the Horizon Europe Programme. As such the project considers the importance of sustainability of financial commitments, the need to test the funding model and to enhance the visibility of the RI. DANUBIUS-IP will further demonstrate the efficacy of an integrated and interdisciplinary approach embracing a 'river-sea continuum' perspective to fill current gaps in the Research and Innovation landscape to address key societal challenges in these environments impacted by anthropogenic pressures and climate change.