During the timespan of the implementation of a system, the why and what against the actual state of the system can change. This difference is referred to as the design problem. Currently, no design problems are identified in Business Rules Management (BRM) and Business Rules Management System (BRMS) literature. To solve problems with a BRMS implementation it is important that the problems solved by this implementation are known, which is not the case. A case study approach is utilized containing two phases of data collection. Phase one consisted of multiple expert interviews focused on creating a set of design problems utilizing existing literature on BRMS design problems. Then, in phase two, the set of design problems were proposed to a selection of thirteen organizations, which indicated if the design problems occurred in a BRMS implementation. This resulted in a set of 24 design problems. The identification of design problems contributes to future research in evaluating BRMS’s. Furthermore, the identification of design problems is a contribution towards situational artifact construction in the field of BRM.