The third Annual Meeting of Open Science Pioneers in Serbia will present a framework for disseminating information about the role of NI4OS-Europe and other EOSC-related efforts in the development of the European Open Science Cloud. Open Science Pioneers are an informal group including various Open Science stakeholders, such as researchers, librarians and institutional decision-makers. The group is permanently expanded to include those who have made a significant progress in Open Science in the past year. This year’s meeting will be organized by the University of Belgrade’s NI4OS-Europe team as an online event and it will particularly focus on the following topics: