The question this essay attempts to answer is what the role of theory is today in the complex world of restoration and conservation. But that is not all. The aim is also to bring back to the centre of the discipline the theoretical nodes, which too often take second place to the design and technical aspects, such as those that give substance to the discussion on heritage and patrimonialisation. Much has been said on the critical formulation of a restoration project, especially today, in the face of global phenomena becoming ever more complex there is a necessity to recuperate the theoretical and notional values of the discipline. Faced with the advancement of technical solutions and the ever-increasing intrusiveness of scientific instruments, restoration risks losing its theoretical foundations. In addition to questions about laboratory investigations, sustainability, climate change issues or the choice of green products, it seems more necessary than ever to return to the more strictly philosophical-humanistic questions that must then necessarily be the foundation of restoration work..