Mention In Despatches 1939-1945:

Mentioned in Despatches (MID) is a military award for gallantry or otherwise commendable service. The award is relatively common, does not confer a medal and is relatively low in the order of precedence.

A despatch is an official report from a senior commander, usually of an army, to his superiors, detailing the conduct of military operations. In the British Armed Forces, this report is published in the London Gazette.  If a subordinate officer or soldier performs a noteworthy action included in the report, he/she is said to have been "mentioned in despatches".

Soldiers of the British Commonwealth, who are mentioned in despatches receive a certificate and are entitled to wear a silver oak leaf (from 19201994, it was bronze, in the Canadian Forces it still is) on the ribbon of the service medal issued to soldiers who served in a conflict. If no campaign medal is awarded, the oak leaf is worn on the left breast of dress uniform.