The hospital reform initiated through an expert opinion of the German research institute IGES places great emphasis on the aspect of outpatient care. In this context, the current IGES guidelines extend further than has previously been the case. There are only very isolated instances where this theoretical potential has been translated into practical application in urology. This study aims to reflect the theoretical potential calculated using real data from urology with a view to practical application. Using the algorithm of the "Hospital Structure Navigator" of DKTIG (Deutsche Krankenhaus TrustCenter und Informationsverarbeitung GmbH), focused on the extension of the AOP (Ambulatory Operations and Procedures) catalogue, section-21 data of the year 2022 from the Clinic for Urology at the University Hospital Schleswig-Holstein was analysed. The inclusion and exclusion criteria provided by IGES were applied, along with a limitation of the length of stay to two days and a minimum case number of 30 cases per year. Since this resulted in a very low potential for target DRGs (Diagnosis-Related Groups), the criteria were further modified. With this approach, a plausibility check for the outpatient treatment capability of identified cases was conducted. After applying the inclusion and exclusion criteria, only one applicable DRG (L18B) emerged, but with the expanded criteria, eight DRGs were identified. From the case flat rates determined, three appropriate OPS codes were identified:1.) Ureterorenoscopic removal of stones from the kidney with lithotripsy (5-550.31)2.) Transurethral resection of a bladder tumour, not fluorescence-supported (5-573.40)3.) Bougienage of a ureter, transurethral (5-560.2) CONCLUSION: With the current set of criteria defined by IGES for urology, no significant outpatient potential can be achieved. However, the expansion of criteria has uncovered areas that could be well implemented with a broader set of criteria and are currently seen more systematically in the realm of measures replacing inpatient procedures or hybrid DRGs. In addition to the need to clarify the fundamental outpatient feasibility of the methods on an individual case basis, there are limitations here, especially for multimorbid populations. Therefore, in expanding the catalogue, the legislator must take into account the higher risk and monitoring effort required for these patients.