The author discusses preventive measures under three general headings: Breakage, Stabilizing Displays, and Heat and Moisture Control. He lists practical procedures such as handling methods, storage, determination of previous repairs, correct and incorrect mounts (Plexiglass). Precautions against vibration and jarring of glass or ceramic objects in display cases are described. Ceramics and especially glass, are affected by changes in heat and moisture. The problems of soluble salts in terracottas and earthenwares and of crizzled or weeping glass are discussed.