Colin Gurner was born in Adelaide in 1919 and educated at Prince Alfred College and the University of Adelaide. He joined the militia (CMF) in 1939, and completed his internship at Royal Adelaide Hospital (RAH) before entering army service in 1943 as a Captain. He served in various Camp Hospitals in both Australia and New Guinea, including AGH 101 near Adelaide where his father was the radiologist. When war ended Colin trained in the radiology department at RAH, acting also as radium officer. After obtaining RACP Membership in 1950 he spent a year as Fellow in Radiation Therapy at Memorial Cancer Centre, New York, obtaining the Diploma of the American Board of Radiology (Radiation Therapy). On returning he joined the long-established radiological practice in North Terrace of Victor Stanley Verco and his father as a junior partner. He maintained honorary appointments to RAH and Adelaide Children's Hospital while continuing his involvement with the CMF, holding a senior appointment and commanding two medical units.

In 1960 following the retirement of Major General William Refshauge as DGMS to become Commonwealth Director of Health, Colin accepted the offer to join the Regular Army as deputy DGMS. He was promoted to Brigadier in 1961 and Major General in 1967 when appointed DGMS. It was a time of National Service in Australia and involvement in the Vietnam War. Colin made regular trips to Singapore, Malaysia and New Guinea where troops were stationed. To be readily available to the Chief of the General Staff and Ministers for the Army, successively Malcolm Fraser, Philip Lynch and Andrew Peacock, Colin moved to Canberra. He was appointed Physician to the Queen in 1967 and Commander of the British Empire in 1969 in recognition of the contribution of the Medical Corps in Vietnam.

Colin Gurner was President of the Royal Australasian College of Radiologists at the time of the First Asian-Oceanian Congress of Radiology held in Melbourne in 1971. He was appointed the first Surgeon General of the Defence Forces in 1977 and Officer in the Order of Australia in 1978. Following compulsory retirement at 60, Colin became director of the Australian Kidney Foundation and returned to radiology working in the Health Department and private practice. He was Chairman of the ACT Medical Board from 1979 to 1984.

Always keen on sport and the outdoors, Colin gained blues in football and cricket at Adelaide University and played district cricket. He once admitted to dropping Don Bradman off a friend's bowling! In his seventies, he completed a diploma of journalism. In 2003 he published The Royal Australian Army Medical Corps, 1945-1975, described by a reviewer as 'a precious document'. Among many other awards he received Honorary Fellowships from the Royal College of Radiologists (London), Royal Australasian College of Physicians and the Royal Australasian College of Surgeons, delivering the Rupert Downes Memorial Lecture in 1979. He was a Knight in the Order of St John of Jerusalem.

Colin's main interests during his Army days included malarial control, innovative means of evacuating those wounded and the effects of chemical, biological and radioactive weapons. He also promoted successfully the introduction to the medical defence services of part-time specialist expertise. Colin was survived by his wife Cynthia, nee Miller, a physiotherapist, three children, five grand-children and one great-grandson.