Radical processes of transformation are changing our cities and landscapes.The traditional instruments of architecture and urban planning are increasingly unable to address new challenges. Urban Catalyst (UC) is an interdisciplinary platform for research and projects to foster public discourse on contemporary urban issues and develop new strategies for planners and architects. This book presents informal public space uses and unplanned urbanism. Featuring projects by Complizen, Kees Christiaanse, Cedric Price, Stalker, Urban Catalyst, and contributions by Azra Aksamija, Arnold Reijndorp, Florian Rotzer, Saskia Sassen."