The spotlight on health impacts of poor air quality and the renewed focus on reducing GHG emissions in recent years provide a strong impetus for cities to seek clean, low carbon transport solutions. When it comes to meeting growing demands for public transport and addressing environmental issues, hydrogen fuel cell (FC) buses offer significant potential. A commercialisation process for FC buses is underway, through which a shared vision has been agreed between vehicle suppliers and their customers. This is based on reducing costs through scale via a phased approach of pre-commercial demonstrations that will provide the evidence for wider uptake of these vehicles in the 2020s. The first step in upscaling FC bus deployment is underway through the JIVE project, which began in January 2017. JIVE 2 is its successor and is Europe’s most ambitious FC bus project to date: 156 buses in 11 cities across six countries. JIVE 2 involves regions with experience of the technology scaling up fuel cell bus fleets (e.g. Cologne), and those seeking to build their knowledge and experience by demonstrating FC buses in small fleets for the first time (e.g. Auxerre). All deployment locations in JIVE 2 share an ambition to increase the size of their FC bus fleets following successful initial demonstrations, hence the participating cities/regions will be natural locations for larger scale roll-out of the technology in the 2020s. A comprehensive data monitoring and assessment exercise will capture the relevant evidence to inform next steps for the sector, and the project’s impacts will be maximised by a high-impact dissemination campaign. This will involve reaching wide audiences via various channels, including a series of international Zero Emission Bus Conferences. The JIVE and JIVE 2 projects together will see the deployment and operation of nearly 300 FC buses in 16European cities/regions, thus providing a sound basis for further development of this sector.