4 Casualty Clearing Station mobilized in December 1939 as one of the medical units of the 1st Canadian Division for service overseas during the second world war.
4 CSS departed Halifax on 30 Jan 1940 embarked in the Empress of Britain and disembarked along the Clyde on 8 February 1940.
4 CCS was sent to Sicily and operated in Catania providing care for sick and injured Canadian soldiers.
23 Med Coy trained to achieve the highest standards and won the Ryerson Trophy each year from 1961 to 1964, and 1972 to 1974.
As a Canadian Forces (CF) Primary Reserve unit, members may serve on a full or part-time basis.
Deployments are voluntary, and personnel continue to serve alongside Regular Force CF members.
The Edmonton unit is based at Brigadier James Curry Jefferson Building, and in Calgary at the Mewata Armoury.