Due to the changes brought by the Bologna Process we observe a large demand for new inform- ation systems supporting the academic processes. The software demanded is not available on the market. We observe large projects in pioneer universities. Because universities have little experi - ence in implementing and operating such systems, it seems to be worth while to examine the es- sentials of organizational information systems. We reflect on essentials of organizational inform- ation systems and derive normative advise for colleagues. After Lehman’s definition of embed- ded systems 35 years ago, we look at very complex systems, embedded into large organizations. The complexity of such system’s software stems from its database, created by the organization’s users. We argue, which functions are part of a campus management system’s core (CMS) and which are not. E. g. ‘E-learning’ or ‘library’ do not belong to it, but need secure and efficient in- terfaces. Because CMS are expensive they should be implemented into an organization evolu- tionary. We show examples of two cases and provide an overview of a reference model of the database’s core.