On 29/5/2024, the 1st MHH Real-World Data Day took place at the MHH, organised and led by Prof. Apfel-Starke from MIT at the MHH and with the support of TriNetX® and IQVIA®. Experts from the University Medical Centre Schleswig-Holstein (UKSH), Lübeck Campus, presented various application scenarios for high-level scientific research with Real World Data (RWD). The Lower Saxony Clinical Cancer Registry (KKN) was represented with a presentation on the creation of care evidence using RWD and the Technology and Methods Platform (TMF e.V.) showed how the use of secondary data can be applied for via the German Research Data Portal (FDPG). TriNetX® presented its global RWD platform and various application scenarios, including for academic research. IQVIA® demonstrated from the perspective of a global CRO how the analysis of RWD can contribute to more targeted planning of projects in the clinical environment. From the point of view of the ZKS, the systematic use of RWD also offers great potential for the planning of academic investigator-initiated studies. The "Real World Data Days" series is to be continued, not least due to the great interest and the very lively interdisciplinary professional exchange.