The global digital network is a whole new urban infrastructure—one that will change the forms of our cities as dramatically as railroads, highways, electric power grids, and telephone networks did in the past. In this lucid, invigorating book, William Mitchell examines this new infrastructure and its implications for our future daily lives. He argues that we must extend the definitions of architecture and urban design to encompass virtual places as well as physical ones, and proposes strategies for the creation of cities that not only will be sustainable but will make economic, social, and cultural sense in an electronically interconnected and global world.