NH3CRAFT aims at fully designing, engineering, developing and demonstrating a next generation sustainable, commercially attractive and safe technology for high-quantity on-board storage of NH3 as marine fuel. Two innovative modular and scalable steel and composite storage tank configurations for 1,000 m3 liquid NH3 at 10 bar and the corresponding auxiliary systems will be installed on a 31,000 Deadweight Tonnage (DWT) multi-purpose vessel. The exact vessel has been designated and provided by a participating major ship management company Additionally, five different types of vessels and corresponding fuel-storage tank concept adaptations will be studied and documented: a SSS bulk carrier, a tanker and a container ocean going vessels, a typical RoPax ferry, and a small Inland Waterways Transportation passenger vessel. An innovative digital platform will integrate all core simulations and models through digital interfaces and will develop an engineering system matrix and specifications for the fuel storage, supply, and piping, monitoring and venting subsystems. Safety and risk assessment for all vessels will lead to the development of safety guidelines and classification rules. NH3CRAFT will showcase the entire NH3 supply chain in order to increase confidence in its use and promote its uptake. LCA and techno-economic evaluation will prove the sustainability and will support further exploitation and commercialization of the innovative solutions. The vision is to pioneer the reduction of GHG emissions by at least 50% by 2050 compared to 2008 and the eventual “elimination of total GHG emissions and air pollution” from shipping (SRIA for ZEWT goals) remaining consistent with the Paris Agreement. NH3CRAFT aspires to help Europe serve societal needs, maintain global maritime leadership, and support an innovation-driven industry with highly skilled jobs, safe, efficient, and sustainable technological solutions, with new international standards, rules, and regulations.