The book provides a series of reflections on the study of architectural preexistences that have matured during the almost thirty-five years of study and research in Italy and Europe. Furthermore, it shows how the discipline of restoration of monuments is all based in architecture, intended in its many-faceted meanings. The methodical approach to the restoration of historic architecture consists in the historical-critical analysis, central nucleus of the study of architecture and is composed by specific in-depth thematic sessions (the historical iconography; the analysis of the constructive features; the constructive model; the volumetric layout; metrological and proportional analysis; the theme of the figurative model; the analysis of masonry; the theme of decorations; spolia and reemployed; comparisons, analogies and differences; the reading of the architectural organism through the synthesis of the monument in time). The author and his team have collected thematic essays on key issues that have great interest [���]