'For gallantry and devotion to duty. During the period 25th February 1918 to 17th September 1918, Captain Dempster held the appointment of Regimental Medical Officer to the Battalion. At all times in the actions and Trench fighting in which the Battalion was engaged Captain Dempster was at his post often under heavy shell fire. Through his ability and administrative capacity, the evacuation of the wounded was carried out with the utmost despatch. At one time, in May 1918, the regimental aid post of our Right Battalion was blown up by shell fire causing casualties to the R.M.O. and his whole staff. Captain Dempster immediately took over the duties of the R.M.O. of the Right Battalion and, until relief came carried on those duties as well as his own. As a R.M.O. his untiring efforts, his utter unselfishness and his devotion to duty were an inspiration to Officers and men alike. No praise is too high for the manner in which Captain Dempster served his Battalion.'
Source: London Gazette
Date: 1 January 1919

Regimental number	3/2877
Occupation	Medical practitioner
Next of kin	Father, Alex Dempster, 87 St David Street, Dunedin
Rank on embarkation	Lieutenant
Unit name	New Zealand Expeditionary Force, 22nd Reinforcements, New Zealand Medical Corps
Embarkation details	Unit embarked from Wellington on board HMNZT 76 on 16 February 1917
	Members of the New Zealand Medical Corps, 22nd Reinforcements, embarked on two ships, 'Mokoia' on 13 February 1917, and 'Navua' on 16 February 1917. Those listed on Nominal Roll No 54 embarked on board HMNZT 'Mokoia', 15 February 1917. For those listed on Nominal Roll No 55, it is not possible to determine on which ship an individual embarked.
Final rank	Captain
Final unit	New Zealand Medical Corps (attached to 3rd Battalion, New Zealand Rifle Brigade)
Medals	Military Cross 'For gallantry and devotion to duty. During the period 25th February 1918 to 17th September 1918, Captain Dempster held the appointment of Regimental Medical Officer to the Battalion. At all times in the actions and Trench fighting in which the Battalion was engaged Captain Dempster was at his post often under heavy shell fire. Through his ability and administrative capacity, the evacuation of the wounded was carried out with the utmost despatch. At one time, in May 1918, the regimental aid post of our Right Battalion was blown up by shell fire causing casualties to the R.M.O. and his whole staff. Captain Dempster immediately took over the duties of the R.M.O. of the Right Battalion and, until relief came carried on those duties as well as his own. As a R.M.O. his untiring efforts, his utter unselfishness and his devotion to duty were an inspiration to Officers and men alike. No praise is too high for the manner in which Captain Dempster served his Battalion.' Source: London Gazette Date: 1 January 1919
Family/military connections	Brothers: 71101 Corporal George Alexander DEMPSTER, 1st Bn, Otago Infantry Regiment, died of wounds, 8 October 1918; 36572 Bruce DEMPSTER.
Sources	Nominal Roll Vol. 3: Roll 55, p. 25