The origins of the spectacular geometric forms and sparkling surfaces of modern architecture from 1918 to 1939. In the first half of the twentieth century, a new kind of architecture appeared across Europe and North America, characterized by plain, often pure white walls; wide windows; flat roofs; and prominent balconies, terraces, and roof gardens. From houses to hospitals, the new architecture featured large expanses of glass and was constructed from steel and reinforced concrete—or designed to look that way—and inspired by a desire to be functional, hygienic, universal, democratic, and economical. Paul Overy explores the contemporary preoccupations with fresh air and sunshine, space, health, and hygiene, and how these concerns became fundamental to the development of new architectural and design practices. Individual buildings—including both little-known and more familiar examples in Europe and the United States by architects such as Adolf Loos, Walter Gropius, and Le Corbusier—are examined within the context of class and social control, luxury and austerity, race and colonialism. Many of them are considered classics, legally protected from demolition or alteration and, in recent years, restored and reconstructed. Illustrated with many unusual photographs that capture the buildings in their early pristine state, Light, Air and Openness is an innovative reinterpretation of the modern movement in architecture and design. 66 illustrations.