Julio Lafuente was born in Madrid in 1921. Soon after, his family moved to Paris, where he studied Architecture at the École Nationale des Beaux Arts. Once graduated, he established his residence in Rome, where he developed most of his architecture, widely recognised and published between 1950 and 1980. As he is recently deceased, there have been several tributes in the Royal Academy of Spain in Rome, the Cervantes Institute in Rome and the Biennale di Venezia 2014, among others. How should the undertaking of both the archive and catalogue of the work of an architect be faced? What methodology should be followed to feature our findings and contextualize his works, publications and projects from different perspectives: context, critical thinking, practice, role, technique? How to interpret the significance of existing documents, such as drawings, models, plans or photographs, not from a documentary point of view but through the eyes of the architect? The purpose of this paper is to share the research results obtained through the compilation process of the Archive of Julio Lafuente, declared of historic and artistic interest by the Italian Ministry of Culture and the unpublished Catalogue of his work, non-existent to date, undertaken by the author of this paper.