Long service life of inland vessels, high investment costs, low re-investment capacity of the Danube fleet operators together with knowledge deficits about green technologies as well as the lack of public actions & incentives impose severe barriers for the adaption of the Danube IWT fleet to forthcoming European IWT and environmental policy objectives. GRENDEL shall support the Danube fleet operators and their public counterparts (ministries & relevant authorities) in the required modernisation process by establishing a transnational cooperation platform of key IWT stakeholders. With the help of dedicated learning interactions, technology deployment preparatory works, as well as guidelines and recommendations leading into a widely accepted overall strategy for Danube fleet modernisation, GRENDEL will contribute to overcome major innovation obstacles. Dedicated activities shall raise the awareness of the sector concerning the impact of new regulations, advanced technologies which reduce air pollutants & energy consumption of inland vessels as well as improved transport & logistics management processes making use of digitalisation. Further to this, GRENDEL will support public authorities in elaborating public support measures (State Aid Model) based on defined investment priorities of most relevant IWT fleet operators in terms of greening technologies, financial volumes and timeline. Special attention is paid to human resources & training requirements of new technologies applied. The solutions elaborated will be shared with the Danube IWT sector as possible blueprints through the established stakeholder platform, thus ensuring the wide capitalisation of the project results. Improving the environmental and economic performance of the Danube IWT industry is the main goal of the project and shall contribute to a higher acceptance and use of the IWT sector as an environmentally friendly transport mode contributing to economic growth & a more sustainable transport system.