One of the greatest misconceptions about self assessment is that it can be undertaken in isolation from others. While it would be possible to envisage self assessment processes of this kind, most examples in higher education require the involvement of other parties. The defining feature of self assessment is that the individual learner ultimately makes a judgement about what has been learned, not that others have no input to it. While there are many strategies which involve staff inputs, most interest and activity has been shown in the role of peers, that is, other students who are studying alongside the learner. How can such people be used most effectively? What guidelines might be adopted for the use of peers in self assessment?