In 2016, a new university hospital merged from three former independent Austrian hospitals started its operation. This paper presents a process model developed to coordinate the IT migration after the merger, using five phases to meet the requirements of the specific setting. A methodological mix of interviews, surveys and workshops was applied during the IT migration process. High stakeholder participation and a transparent methodical approach led to a broad agreement on success factors, migration objectives, and evaluation results. Thus, acceptance for the finally selected migration scenario was very high among employees, which is known to be crucial for the success of migration projects.