EOSC-Pillar aims to coordinate national Open Science efforts across Austria, Belgium, France, Germany and Italy and ensure their contribution and readiness for the implementation of the European Open Science Cloud (EOSC). The project aims to support the coordination and harmonization of national initiatives relevant to EOSC in Europe and investigate the option for them to interfederate at a later stage, help integrate initiatives and data/cloud providers through the development of common policies and tools, and facilitate user communities in adopting and using these services and propose new ones born from their scientific domain.