Nanoscience and nanotechnology are revolutionizing materials science in a pervasive way, in a manner similar to polymer chemistry's revolution of materials science over the preceding century. The continuous development of nanosized materials and the study of physicochemical phenomena at the nanoscale are paving the way for novel strategies of conservation, leading to methodologies that may “revert” the degradation processes of the works of art. In this entry, synthetic pathways of alkaline earth hydroxide nanoparticles, specifically tailored for the preservation of cellulose‐based artifacts, and their applications to historical and artistic materials have been reviewed. These new methodologies have been shown to be safer, simpler, and more reliable and effective than traditional methods for the preservation and restoration of artifacts.