Air Architecture presented, for the first time, Yves Klein’s architectural projects and theories with particular regard for his exploration of the void and its utopian implications as they applied to an immaterial architecture. Relying upon technology and the use of the four elements—air, water, fire and earth—Klein envisioned a world in which man lived in harmony with the natural elements through the mechanisms of Air Architecture. Famous for his blue monochromes and provocative performances, Klein had a special interest in architecture as an extension of his practice. With the help of several architects, he designed several projects that were never realized, largely due to his premature death at the age of 34.