We implemented a framework for modelling the electronic medical record on top of an object-oriented model. Clinical patient data are structured in a uniform way through the use of a comprehensive data model. The meaning of the information elements is explicitly determined by a medical data dictionary. The data structures of both, medical record and data dictionary are implemented, using a semantically rich, object-oriented data model. We examined several possibilities for the graphical preparation of the inherently recursive data structures. Again, we use object-oriented frameworks for the implementation of flexible user interfaces to the electronic medical record with a consistent look-and-feel.