The concept of assessment has broadened and has multiple purposes. There has been a move away from comparison/competition among students to what has or has not been learned; a greater emphasis on criterion-referencing than peer-referencing. Table 1 highlights the essential differences between these two models of assessment. The challenges in criterion-referenced exams include the need to make sure all the judges make the same judgement about the same performances (i.e. inter-rater reliability), constructing appropriate criteria that are evidenced-based and pragmatic, defining criteria unambiguously, applying criteria fairly, and minimizing examiner differences.