Bacause of the vastness of the illustrations, the two Zevi's books could be titled "Encyclopedia of Modern Architecture," and it should be, among encyclopedias, the most comprehensive and current. Also because it includes the entire urban development, the great works of the nineteenth-century Paris, Vienna, Madrid to the British and Scandinavian New Towns, and future projects of the city.
 

The first volume documents the origins of the modern movement (from the French Revolution onwards), the first pioneering age with Arts and Crafts of Morris and the Horta's Art Nouveau, van der Velde, Olbrich, Gaudí and Loos, the rationalist period marked by Le Corbusier, Gropius and the Bauhaus, Mies van der Rohe, Mendelsohn and expressionism, finally the organic season with Aalto.
 

In the second volume the story expands with the American organic movement, enhanced by the genius of Frank Lloyd Wright, and with the complex linguistic contributions of the last 45 years, fermented by Scharoun, Pietilä, Utzon, Gehry. Modern architecture is becoming more differentiated, without losing its identity.