Historically speaking, students were judged long before they were marked. The tradition of marking, or scoring, pieces of work students offer for assessment is little more than two centuries old, and was introduced mainly to cope with specific problems arising from the growth in the numbers graduating from universities as the industrial revolution progressed. This paper describes the principles behind the method of Comparative Judgement, and in particular "Adaptive" Comparative Judgement, a technique borrowed from psychophysics which is able to generate extremely reliable results for educational assessment, and which is based on the kind of holistic evaluation that we assume was the basis for judgement in pre-marking days, and that the users of assessment results expect our assessment schemes to capture.