In the context of the visiting professorship of Prof. Dr. Thomas H. Kolbe at TU Delft, the entire team of the chair took the opportunity for an exchange and followed the invitation of Prof. Jantien Stoter and Prof. Peter van Oosterom to TU Delft. In addition to a visit to the city administration of Rotterdam, where the strategies for the 3D city models of Rotterdam and The Hague were presented and discussed, participation in the OGC meeting in Delft was on the schedule. The focus of the trip was a two-day joint doctoral seminar with the aim of identifying possible co-operation and research fields and promoting the exchange between the two teams from TUM and TU Delft.