This paper describes how an urban commons is established on the Amsterdam market square Plein ’40-’45, to explain how an experimental learning environment can be a living lab for improving collaborative governance arrangements. We detail how this improvement is facilitated by an experimental learning environment that engages stakeholders in a process where practical solutions are developed and systemic obstacles are addressed and redesigned simultaneously. Our study is guided by the research question: How can an experimental learning environment develop practical solutions as a means to address systemic obstacles and improve collaborative governance arrangements?