The course (module) grades entered on higher education academic records (transcripts) purportedly represent substantive levels of student achievement. They are often taken at face value and accepted as comparable across courses. Research undertaken over several decades has shown that the underlying standards against which student works are appraised are poorly understood and can vary widely from assessor to assessor. At the same time, it is commonly held that academic judgements should be respected and form the basis of any quality assurance scheme. This article is about some of the conceptual foundations relevant to a particular approach to assuring academic achievement standards. The final concept discussed is that of "calibrated" academics who are able to make grading judgements consistent with those which similarly calibrated colleagues would make, but without constant engagement in moderation. The overall aims are to achieve comparability of standards across institutions and stability of standards over time.