During his 35 years in full-time practice, Faunce became recognised for his diagnostic skills, for his high standards of professional ethics and his concern for the medical, personal and social needs of his patients. Trainee Bill Burke (now a Canberra respiratory physician) stated: "Ebullient, military in his gait and bearing, [Faunce] was prone to swing onto the ward stepping out to his own loudly-whistled accompaniment of the
Colonel Bogey march. He was knowledgeable yet always looking to expand his knowledge, and his visits to the patient's bedside in even the most dire circumstances had a therapeutic effect seldom available in the pharmacopoeia." Faunce was individually selected to be honorary personal physician to five Prime Ministers (including
Gough Whitlam and
Malcolm Fraser) and six Governors-General (including Sir
Zelman Cowen, Sir
Ninian Stephen, and The Hon.
Bill Hayden). Faunce was Prime Minister
Harold Holt's personal physician at the time of the latter's
disappearance in the surf at
Portsea; his treatment at that time of Holt's shoulder injury and refusal to prescribe
opiates featured in the 2008 film
The Prime Minister is Missing. In 1959, Faunce and fellow physician Tony Proust founded the Canberra Medical Society, whose meetings were initially held in the
Howard Florey lecture theatre of the
John Curtin School of Medical Research, through the courtesy of its director. Marc served on the ACT Medical Board from 1963–74 and was senior physician consultant to the
RAAF Medical Directorate from 1976–1980 with the rank of
group captain. Faunce was largely responsible for the creation of the Department of Respiratory Medicine at the
Royal Canberra Hospital in 1978. == Honours ==