Peter Sullivan wintered at Davis in 1983 and 1985, taking on the role of Antarctic Medical Officer with an unflagging and selfless devotion to the welfare of the expeditioners. His sense of humour, friendliness and professional competence made him a pivotal member of any group in the field or on station. He promoted harmony amongst the members by his genuine warmth and interest, was a key figure in group activities and played a leadership role as the Second-in-Charge.