Open Science (OS) is a European policy to practicing science in a way that increases openness, integrity and reproducibility of research. This presentation will address challenges and opportunities brought by Open Science and how the European Open Science Cloud (EOSC) will be implemented in the next ten years. In particular, it will illustrate the role of EOSC in deepening the European Research Area (ERA), notably by continuing to federate across Europe research data infrastructures and services and to foster open and collaborative knowledge and data sharing and interoperability so as to progressively enable a trusted, secured and functional research and innovation data space and service platform in Europe.