The University of Duisburg-Essen (UDE) was founded in 2003 as a result of the merger of two universities. Bringing great changes to a venerable institution, the merger provided an opportunity to introduce new internal quality assurance (IQA) structures. Influenced in part by a continuation of earlier quality-related activities, and also by new legal requirements for programme accreditation by the German authorities, UDE has established an IQA system that interconnects existing tools and follow-up procedures in order to maximize its contribution to the system as a whole and feed evidence into decision-making and change. Conducted within the framework of an international research project implemented by the UNESCO International Institute for Educational Planning (IIEP), this case study focuses on the challenges and limitations of systematizing IQA processes into a system, and the effects of IQA on the university.