This interpretive report reviews the literature on stress-relief cracking in austenitic stainless steels, ferritic creep-resisting steels, and low-alloy constructional steels.The review provides a survey of research investigations and testing methods and also points out areas where further research is necessary.Since the ferritic and constructional steels are of greater practical interest today and have received more attention in the literature, they are discussed in greater detail than the austenitic grades.Stress-relief cracking is defined as intergranular cracking in the heat-affected zone or weld metal that occurs during the exposure of welded assemblies to the elevated temperatures produced by postweld heat treatments or high-temperature service.Because this type of cracking can occur not just during stress-relief heat treatments but during elevated temperature service as well, it has also been referred to in the literature as post-weld-heat-treat cracking and reheat cracking.In any case, for such cracking to occur there must be some relief of stresses by creep at the elevated temperature involved. Indeed, in most cases cracks develop only over a specific range of temperatures.