Urban transformations provide significant opportunities to foster circularity transitions. However, this potential creates a tension with the broader strategic aims of said urban transformations. Within this landscape, this thesis looks at how Living labs – a form of urban circular experimentation – influence the spatial planning practices that need to find a balance between the sustainability demands and the economic demands of space. This thesis uses the conceptual understanding of the living lab as an environment and an approach to explore the ways in which planning strategy and planning form are influenced. For this, a case study of Buiksloterham is employed. Buiksloterham housed a living lab from 2014 till 2021. It was found that the living lab managed to influence planning strategy on a specific level. Furthermore, a circularity discourse has disseminated towards the systemic levels of planning strategy. However, whether or not this living lab can be causally linked to this dissemination as a catalyst, cannot be fully disclosed. The transformative potential of the living lab is found in its ability to muster a transdisciplinary community of powerful actors that collectively can claim a space for an exemplary project. However, it depends on the professionalism of the organizational core of the lab whether this mustering of stakeholders is successful.