PART 1 At the time this incident occurred, I was running 'Anatomy of the Head and Neck' in a PBL format for the first time after having presented it in a traditional didactic fashion for five years. There were 49 students in the class, divided into six groups by self-selection, each group comprising 5 to 12 students. Class contact consisted of twice-weekly PBL sessions, while the subject assessment included elements of peer-and self-assessment, together with problem-based viva assessment sessions. The peer-and self-assessment was worth 30 per cent of the overall assessment for the subject and was derived solely from the students' grading, without direct input from the tutor. Because there were many student groups and several tutors, the tutors found it difficult to gain sufficient exposure to all the students, and this affected oversight of the peer-and self-assessment process.