3D BAG is our open data service that contains automatically reconstructed models of all buildings in The Netherlands. The models are frequently downloaded and used in a variety of urban applications. The current version of the 3D BAG data service has been developed in a EU-funded research project ‘Urban Modeling in Higher dimensions’. Recently a proof of concept project has been awarded by Horizon Europe to assure both the technical and economical sustainability of 3D BAG as up-to-date and open data service. The project is a collaboration between the research group and the spin off 3DGI (started by Ravi Peters and Balázs Dukai, two former team members and main developers of 3D BAG). To assure technical sustainability of 3D BAG, the project will address issues such as supporting more height data sources (other than only LiDAR), preparation for the maintainability and performance of our method in an operational setting and aiming at even higher adoption (e.g. in more domains). Economically, we will explore how to best ensure the sustainability of 3DBAG as an open data service by clarifying the IPR and licensing strategy and assessing the market potentials of value added services and possible international expansions. For the project a researcher will be hired in the research group to extend the reconstruction method for height data extracted from images acquired using photogrammetry (in addition to the currently supported LiDAR point clouds) and to fill in no-data gaps in the input elevation data caused by occlusion effects during acquisition using eg. deep learning. The project will run from 1 September 2022 till 1 March 2024 and will result in three new 3D BAG data releases. See also our project page.