The world's growing vulnerability to planet-sized risks invites action on a global scale. The World as an Architectural Project shows how for more than a century architects have imagined the future of the planet through world-scale projects. With fifty speculative projects by Patrick Geddes, Alison and Peter Smithson, Kiyonori Kikutake, Saverio Muratori, Takis Zenetos, Sergio Bernardes, Juan Navarro Baldeweg, Luc Deleu, and many others, documented in text and images.