This conclusion presents some closing thoughts on the concepts covered in the preceding chapters of this book. The book provides a comprehensive overview of the construction materials and techniques usually encountered in conservation projects. It reviews the importance for the intuitive comprehension and quick assessment of historic structure stability, the limit theory. The book illustrates the main damages and collapse mechanisms in masonry buildings. It describes the modern/scientific approach to structural issues as recommended by International Scientific Committee for the Analysis and Restoration of Structures of Architectural Heritage. Experts accept today that every monument constitutes a ‘genuine’ problem and that no general or universal conservation and restoration methods or criteria exist. However, and due to the important uncertainties and data limitations normally encountered in the study of ancient constructions, subjectivity is possible. Due to it, experts’ personal judgement is of critical importance.