Evaluates the chemical products used in the consolidation and protection of stone in monuments, etc. Firstly, the pre-requisites and criteria for chemical products are reviewed - full knowledge of possible reactions, reversibility, no further damage. Classifies products into two general types of material - remineralizers - silicic acid, sodium silicate; and polymeric synthetic resins as consolidants - epoxy resins, polyesters, acrylic resins. The fundamental causes of stone deterioration are identified as water and humidity. Detailed tables summarize the main properties of the most frequently used consolidants and protectors for stone and stone materials. -- ICCROM