John Clark studied philosophy, politics and economics at St Peter's College, Oxford. After four years as head of economics at Ellesmere College, he joined Eton in 1982. He served as head of economics and politics (1988 - 1992) and house master (1993 - 2006). From 2006 - 2009 he was headmaster of Mvumi Secondary School in Tanzania.
The role of Senior Tutor is to supervise a team responsible for the induction, appraisal and professional development of masters and to provide a conduit between masters and senior management.