This case study shows how Die Bremer Stadtreinigung (Bremen City Sanitation Services) reintroduced digital invoice processing after migrating to SAP S/4HANA using an xSuite solution. By automating invoice capture and approval workflows, the organization significantly reduced processing times and improved transparency. The solution enables centralized tracking, clear responsibility assignment, and efficient collaboration through SAP Fiori apps. Readers gain insights into how public sector organizations can enhance efficiency, traceability, and control in accounts payable processes.