This publication brings together all of the architect's unbuilt works. Organised into 2 volumes, the first includes a variety of texts by invited or remembered authors, some essays, others memoirs, or testimonies of specific moments or events, to which Álvaro Siza's texts referring to unbuilt projects have been added. The second volume compiles all these projects, duly identified, with a short text as well as images, sketches, photographs of models and accurate drawings at various sca.