The Meritorious Service Medal was introduced on 19th December 1845, and was typically awarded by British military authorities as a means of formally recognising long military service or given acts of merit.
The MSM (as it was known) was awarded to warrant officers and senior NCOs. Such servicemen were eligible for the award once they had received their army discharge after a period of at least 21 years.
With the vastly increased demand for medals generated by the First World War the MSM was, from 1916, also awarded for acts of gallantry or meritorious conduct when not in the face of the enemy (in which event other medals such as the V.C. and M.M. were available).
The MSM is made of silver, 36 millimetre diameter and has the profile of the sovereign on the obverse and the reverse side has a crown and wreath around the words "For Meritorious Service". The recipient's details are shown on the medal's rim.
The ribbon has undergone 3 designs since the medal introduction. From 1845 to 1916 it was Crimson only, from 1916 to 1917 it was Crimson with white edges, and 1917 onwards it was Crimson with white edges and centre stripe.
The medal was introduced, with an annual annuity (£20 per year), to recognise meritorious service by Sergeants and other senior NCOs. From 1956, recipients must have completed a minimum of 27 years service. The number of awards that could be made in a particular year was therefore limited by the amount of annuity. However, from 1951 the MSM could be awarded as required with the annuity paid when funds became available.
The gallantry portion was cancelled on 7th September 1928 because the British Empire Medal now served this purpose. The King's Regulations and Order's of 1939 listed the MSM and stated that it could be awarded to a soldier of the active militia who is recommended on account of gallant conduct in the performance of military duty (not necessarily on active service) or in saving or attempting to save the life of an officer or soldier, or for devotion to duty in a theatre of war.