Public health concerns in Europe demonstrate the necessity of building a health policy that could contribute to the long-term sustainable development of the European Union (EU), as stated in the European Health Union (EHU) manifesto. The main desire to create an EHU is embodied in the launch of the European Health Data Space (EHDS). The EHDS seeks to foster a genuine single market for digital health services and products by, among other things, accelerating the uptake and implementation of harmonised and interoperable electronic health record (EHR) systems across the EU. In the context of primary and secondary use of EHR data, developments in Europe have thus far resulted in patchy and, in some places, non-interoperable solutions. Taking the gap between international ambitions and national realities as a starting point, this paper contends that both EU level and Member State level circumstances should be considered to make the EHDS a reality.