Presentation of Case Studies from the FAIRCORE4EOSC Project, presented at the FAIRFest in DenHaag, 20.- 21. February 2025. The FAIRCORE4EOSC project is developing and realising FAIR enhancing services for the European Open Science Cloud (EOSC). Leveraging existing technologies and services, nine new services aim to improve the discoverability and interoperability of an ever-increasing amount of research outputs. To ensure that these new services are co-designed and tailored to the needs of their future users, five case studies led by thematic and data infrastructure EOSC communities drove the development and testing of the new components. In the FAIRCORE4EOSC Case Study session, these case studies presented their work, showcasing the test implementation of the new services for FAIR data management to an interested audience and told about their lesson-learnt. Diverse approaches to enhancing data stewardship across various disciplines were highlighted and allowed fresh and exclusive insights into the practical data management work of several EOSC communities. The Case Study representatives Maxence Azzouz-Thuderoz (Mathematics), Joonas Nikkanen (European Integration of National-level Services), Chris Ariyo (Service Providers and Research Data Management Communities), Willem Elbers (Social Sciences & Humanities) and Beate Krüss (Climate Change) demonstrated, how the FAIRCORE4EOSC services can make life easier for research data managers and data stewards through enhanced machine-actionability, as well as improved findability and metadata quality for researchers and infrastructure managers in their respective fields.