This article provides an insight into the value of "Grains of Truth" and "inside information" to underpin the assessment and prediction of materials performance in engineering components and structures.

A knowledge of how the "big four" (microstructure, mechanics, environment and timescale) influence materials behaviour is emphasised. The existing approaches of engineering assessment methods, mechanistic modelling and features testing are described. Selected major challenges faced by the Materials Engineer working in the nuclear industry are summarised alongside some of the emerging experimental and modelling approaches. Interdisciplinary working, in which material scientists, engineers and corrosion specialists (for example) combine forces, is highlighted as a particular innovation which, the author maintains, warrants serious consideration.

The Materials Engineer is now working within the context of "Keeping the Nuclear Option Open", where new initiatives in industry and academia are providing new opportunities to underpin the assessment of engineering components and structures with the fundamental research that yields the essential "Grains of Truth" and "inside information".