The derivation of specific models from reference models corresponds with the creation of reference model variants. Research on the design of such variant constructions generally assumes an unchangeable stock of reference models. The potential inherent in the management of these variant constructions which reflect the changes in jointly designed reference models through time and, in doing so, their evolutionary development, has not yet been tapped into. The article at hand analyzes this problem and presents a concept for the version management of jointly designed reference models as a solution. The task to be mastered with the proposed approach will be concretized using data structures and a system architecture and then prototypically implemented.