How is BIM implemented and integrated as a building process for existing buildings on a social and organizational level? By researching the building process at Schiphol during the project upgrade Wortel g-pier and combining these results with theoretical knowledge of BIM, a hypothesis could be written with a potential method of implementing and integrating BIM. This hypothesis could then be implemented and tested for the project upgrade Wortel g-pier at Schiphol Airport. The results of the implementation of the hypothesis could then be generalized to all projects where there would be an existing building.