[2] At the outbreak of war in September 1939 he volunteered for service with the Royal Army Medical Corps (RAMC) as a surgical specialist.

Early in 1944 he was posted to the Anzio beachhead with No 15 Casualty Clearing Station and for his services there he was awarded Membership of the Order of the British Empire (MBE).

[3] After demobilisation in 1945 with the rank of Lieutenant Colonel he returned to Edinburgh and worked initially in the University Anatomy Department where he produced the thesis for which, in 1947, he was granted the degree of Doctor of Medicine (MD).

When the  National Health Service was founded in 1948 he acquired the new designation of Consultant Surgeon and took charge of the Surgical Out-Patient Department.

Ross was largely responsible for the establishment of the college's triennial overseas meetings and was a prime mover in the reform of higher surgical examinations together with the orthopaedic surgeon Professor JIP James and the neurosurgeon John Gillingham.

The early proposals were refined under his successors and ultimately resulted in the institution of higher intercollegiate examinations in the surgical specialties.