There are many situations where high temperature sulphidation is a serious problem.The wide-spread occurrence of sulphur in some fossil fuels and the presence of sulphur oxides and other sulphur-containing species in many combustion atmospheres derived from fossil fuels promote unavoidable damage due to sulphidation.Sulphidation attack is particularly severe in environments of low oxygen (pO2~10-18 Pa) and high sulphur (pS2~10-1 to 10-3 Pa) potentials at temperatures >700oC.Such a mode of attack cannot be substantially inhibited even by the highly developed oxidation resistant alloys and coatings.