For several years, public spaces have been experiencing an upswing, in political debates and in debates in the media, as well as in the intrinsically transdisciplinary contexts of urban research and development. In these scientific and practice-oriented domains, the manifold challenges of this complex and dynamic construct are, for the most part, being acknowledged and discussed from diverse perspectives, with different epistemological interests. Here, the establishment of transdisciplinary scientific initiatives and strategies of governance which, with various biases and desires, accept the specific public spaces, or that deal with social, architectural, economic, political, aesthetic, artistic, and cultural dimensions and interrelations at a theoretical and practical level, can also be seen to an increasing extent. Debates and processes of this very nature are then often situated at interfaces between fields of responsibility that were previously more clearly marked out.