The way we work and the demand for offices is changing in the Netherlands. This poses the question whether the traditional office park is still viable. However, the demand for housing provides an opportunity to transform these outdated office parks into new mixed-use areas. This way the quality of the area could be improved, and the area could be utilised better in a time when demand for is high and available land is scarce. The literature shows that the transformation of office buildings to mixed-use can be successful. However, there is a lack of research on how this transformation process of office parks into mixed-use works on an urban area level. There is a lack of insight into the landowners and other actors in the transformation process. The available literature shows that landowners can oppose this transformation. The research design used is triangulation, utilizing multiple research methods to arrive at a conclusive answer. The research commenced with conducting a literature review, supplemented by an exploratory interview with a private investor, in order to establish a basis for the research. Case studies were then conducted, followed by a cross-analysis. Finally, an expert panel was conducted to verify the findings and to gain further insight into the research topic. This research, limited to the context of the Netherlands, aims to identify where the transformation process of office parks is hindered and to gain insight into the process and the roles played by different stakeholders. The objective is to provide municipalities with recommendations on using policy and regulations to entice market parties, particularly landowners, to initiate the transformation process. The results show that it is possible to use the same strategy for transformation projects on a higher abstraction level, however it needs to be flexible to respond and adapt to the location characteristics.