Hubert Lehner is Head of Division for 3D Modelling & 3D Services at the City of Vienna in the Department Surveying and Mapping. In this position he is responsible for data modelling of 3D geodata products for the City of Vienna as well as providing 3D services for other departments. He is in the project lead of the Digital geoTwin - a virtual, semantic 3D replica of Vienna. The project aims at transforming the geodata production of Vienna towards a Digital geoTwin, which enables to derive all relevant data sets from it and serves as basis for a city information model and a living Digital Twin of Vienna.