Background <p>Fragmented and locally siloed data limit progress in critical care research and education. The European Health Data Space (EHDS) proposes a federated, privacy-preserving framework to connect intensive care units (ICUs) across Europe. Sepsis is an ideal model condition given its heterogeneity, high mortality, and persistent gaps in standardization and outcomes.</p> Objectives <p>This narrative review explores how federated and synthetic data can transform sepsis research, quality improvement, and education within the EHDS. It aims to outline both the opportunities and practical limitations of building a European-wide, learning ICU network.</p> Methods <p>Recent literature, European policy documents, and federated data initiatives were reviewed to synthesize conceptual, technical, and ethical aspects of implementing federated learning in intensive care.</p> Results <p>Federated infrastructures enable joint analysis of distributed ICU data without sharing patient-level information, supporting benchmarking and surveillance while maintaining privacy. Synthetic data add value for simulation, algorithm testing, and training but cannot replace real-world complexity. Major barriers include data harmonization, interoperability, and governance. Ongoing projects demonstrate that transparent, secure frameworks can make responsible data sharing feasible.</p> Conclusions <p>The EHDS offers a realistic foundation for connecting ICUs across Europe through ethically governed federated systems. Combining clinical, engineering, and data science expertise will be key to transforming fragmented ICU information into shared intelligence that supports sepsis research, education, and personalized critical care.</p>