Process orientation has been established for decades and also plays an important role in the digital transformation of public authorities. In contrast to private companies, however, they face specific challenges due to their structures and objectives. These challenges include aspects such as transparency, external regulation and measurement against the benchmark of citizen performance. This paper examines the challenges and success factors in the introduction of business process management (BPM) in German public authorities. Specific insights were gained through a three-stage Delphi analysis with two selected experts from the public sector. The identified success factors are discussed along the 7S model. The role of existing organizational units and established processes can serve as a basis for the introduction of process orientation and a process-oriented view across systems requires special attention to interfaces, especially in cooperation with private and public institutions. Shared values are crucial for inter-organizational cooperation. Human resource aspects, including the recruitment of skilled staff and flexible pay structures, have a decisive influence on the success of process implementation in the public sector. In summary, the results of this article not only highlight challenges, but also offer BPM experts from the public sector environment many tried-and-tested approaches for their own work on process orientation.