The aim of this chapter is to reconstruct the study of lay judgement from the perspective of the practical concerns orientation. It is claimed that the study of lay judgement under the lay scientist analogy, while not wholly wrong, has obscured the issue by treating judgement out of its natural context and by using unrepresentative types of problem and categorisation of lay judgement. Judgement should be considered from the point of view of its function, not that of its scientific accuracy, or the degree to which judgemental processes succeed in modelling normative scientific procedures. The main role of judgement is to assess the extent to which some state of affairs, course of action, or decision, real or hypothetical, satisfies some standard set by the practical concerns of the judge at the time of judgement, thus acting as a guide to behaviour or decisions aimed towards satisfying that standard. It is wrong to assume that lay judgement either does or should have any resemblance to scientific judgement.