This paper represents a brief review of a selection of semi-nondestructive, nondestructive techniques designed to assess a materials in-service toughness degradation in the elevated temperature regime. Such an assessment in one prerequisite in arriving at realistic life evaluations of high temperature components. Both the auger electron spectroscopy (AES) and analytical electron microscopy (AEM) have shown some potential, but, to-date, AEM is not really a practical method, for measuring, from both a quantitative and reproducible viewpoint, monolayer type elemental segregation. The Electrochemical Polarisation Kinetic Reactivation (EPR) test and the chemical etching techniques have been continuously developed over the past decade and represent attractive, totally nondestructive, toughness degradation assessment techniques. Discussed are some of the limitations of the EPR test. Chemical etching techniques have demonstrated unique relationships between FATT; the shift in FATT, and such parameters as grain boundary groove width, M, replica surface roughness, R max , and grain boundary ratio factor D o /D a where D o is austenite grain size revealed by a nital etch and D a is grain size revealed by a picric acid etch. They exhibited excellent potential in the field of the practical nondestructive assessment of grain boundary embrittlement whether as a result of phosphorus (Ferritic steels) or carbide or sigma phase precipitation (Stainless steels). Finally, it has been shown that the recent development of a miniature sample sampling technique now makes the small punch test an attractive technique for assessing the material toughness of critical plant locations. Indeed, the small punch test exhibited the least data scatter in the prediction of FATT than do other indirect methods utilising composition and grain boundary evaluations.