Mr Johnston is a consultant transplant and general surgeon practicing at the Royal Infirmary of Edinburgh and Shawfair Park Hospital. His primary clinical interests are liver transplantation, management of complex gallstone disease, hernia surgery and advanced endoscopy (ERCP).

Mr Johnston is also currently the clinical lead for the Edinburgh National Organ Retrieval Service, chair of the UK NORS Clinical Leads’ Forum, Lead Educational Supervisor for transplant surgery training in Edinburgh and Programme Lead for the Edinburgh Transplant Surgery Fellowship.

Notable awards include the Hunterian Lectureship from the Royal College of Surgeons of England and the Sir Roy Calne Award from the British Transplantation Society. He has also received the Professor Kenneth Fearon Memorial Medal, Chiene Medal, Syme Medal and Ker Memorial Prize for research arising from his PhD Thesis.