The Efficiency Medal was instituted in 1930 for award to part-time warrant
officers, non-commissioned officers and men after twelve years of efficient
service on the active list of the Militia or the Territorial Army of the United
Kingdom, or of the other Auxiliary Military Forces throughout the British
Empire. At the same time a clasp was instituted for award to holders of the
medal upon completion of further periods of six years of efficient service. It
was replaced in Canada by the Canadian Forces Decoration in 1951.