This book represents the conclusion of the artistic research project Transient Senses, based on the German Pavilion designed by Mies van der Rohe at the Barcelona World s Fair in 1929. Through a sound installation in the pavilion and experimentation with video, audio, and text, exhibited together in the Fundació Antoni Tàpies, Alex Arteaga explores the formation of the concepts of interiority and exteriority in architecture. The book includes a general description of the project and its context, as well as the original text and essays by Lluis Nacenta (the curator of the project) and the author himself, accompanied by documentary photographs and links to the audiovisual experiments.