This article reviews the efficacy and risks from using thermal control methods for the protection of cultural property. Thermal methods are attractive as they leave no residues, are inexpensive, and applicable to many scales of problem. For many organic materials and assemblies, the risks from thermal techniques are eliminated by the simple act of enclosing objects in a vapour barrier prior to treatment. The magnitude of the risks and possible mitigation procedures for common materials are discussed. A procedure developed for applying solar heat for insect extermination in textiles is given as an illustration. -- ICCROM