These two volumes provide a comprehensive documentation of the creative processes which underlie Santiago Calatrava s diverse and prolific architectural ouput, featuring his personal thoughts, unique documents and analyses. The first volume presents Calatrava s doctoral thesis which combines the varying disciplines of engineering, mathematics and architecture. In the second volume, three of Calatrava s key sketch books are presented, capturing the essence of his more experimental, biomorphic, surreal, metaphorical, and analogical thinking. In this publication, the editors examine the hypothesis that both analytical and analogical tendencies are evident in Calatrava s creative work. The volumes provide a unique glimpse into the mind of this architect where opposites seem to form a rare synthesis and give rise to works of the highest quality.