Knowledge exchange (KE) is increasingly important in higher education internationally, yet relatively little attention has been paid to it as a pedagogic opportunity for students. This paper draws on 26 interviews with stakeholders within and outside HE to develop a model of student-led knowledge exchange as a guide for learning through KE. The model includes the following elements: Preconditions, Prior Knowledge, Planning and Place, Pedagogic Context and Product, and offers an analysis of different forms of KE which occur between individuals in a learning triad consisting of student, facilitator and external participant. The research foregrounds a social view of learning where valid knowledge comes from diverse participants in the exchange, including students themselves. Students act as a catalyst for multi-directional KE -- a finding which challenges the implied hierarchies evident in much of the literature on this topic. The model is offered as a starting point for developing a pedagogy of KE in higher education.