The Corps of Royal Canadian Engineers expanded dramatically in size to support Canada's war effort. On August 31, 1939, the Permanent Force engineers included 50 officers (with 14 seconded to other branches of the Canadian Army) and 323 other ranks; the maximum size of the Corps was reached in 1944, when it included 210 officers and 6283 other ranks.
In keeping with British Army practice, company-sized units in the two armoured divisions were called "squadrons" following cavalry terminology. The following units were deployed in Canada and in Europe: