The continuously accelerating phenomenon of urbanization continues to be one of the great challenges of our time, surfacing repeatedly as an issue in different areas of the world for two hundred years. In a world that has been redefined by a proliferation of communication networks and by a progressive erasure of borders, Mutations reflects on the transformations that these accelerating processes inflict on our environment, and on the spaces in which architecture can still operate. Organized as a heavily illustrated atlas/survey of contemporary urban landscapes, the first section of this exhaustive and essential book begins with revealing data on global urbanization, juxtaposed with a series of essays on the changing environment and economy of today's metropolis. The rest of the book is devoted to a selection of groundbreaking studies by some of the central figures in contemporary architectural urbanism, including the Pearl River Delta in Southeast Asia, a project of the Harvard Project on the City, directed by Rem Koolhaas; ''Uncertain States of Europe, '' a project by Stefano Boeri and Multiplicity; a survey of American cities by Sanford Kwinter and Daniela Fabricius; and a study of Lagos, Nigeria--one of Africa's largest cities--by the Harvard Project.