Francis Alÿs is one of the world's leading contemporary artists and was born in Belgium in 1959. After studying architecture in Venice he moved to Mexico City, where he has lived and worked for almost two decades. Alÿs works in many media, including performance, painting, animation, slides, video and drawing, and at scales from the humblest work on paper to the monumental staged performance. Much of his work draws on the life in the streets around his studio, where people sleep, eat, and make a living. He closely observes these activities while making walks through the city, which are often the genesis of future ideas. His collaborations have involved participants as varied as Mexican sign-painters and British Guardsmen. In 2002, he enlisted the help of 500 volunteers for a performance entitled When Faith Moves Mountains, in which an attempt was made to move a large sand dune one foot from its original position with the aid of shovels. Featuring an introductory essay by Mark Godfrey, an interview with Alÿs by Klaus Biesenbach and descriptions of works in the exhibition written by Alÿs and Cuauhtemoc Medina, the book will also include responses from a wide range of critics and commentators. Published to accompany the largest and most important retrospective exhibition yet staged of Alÿs's work, this will not be a conventional monograph, but will, in the spirit of Alÿs's wandering practice, more closely resemble a guidebook than an exhibition catalogue.