Presents an overview of stone conservation philosophy and outlines the various treatments, from emergency action (temporary consolidation, provisional shelter, etc.) to damage diagnosis, cleaning, consolidation, repair, and final protection. Discusses the performance of inorganic and organic consolidants, illustrates techniques for grouting and fillings, points out the dangers in the use of metal reinforcement. The performance of both hydrophobic and non-hydrophobic coatings is discussed in detail. Environmental protection and regular inspection and maintenance are recommended.