|Distinguished Service Medal|
|Awarded for||Set an example of bravery and resource under fire at sea|
|Presented by||UK and Commonwealth|
|Eligibility||Royal and Commonwealth Naval ratings|
|Status||Discontinued in 1993|
|Established||14 October 1914|
|Order of Wear|
|Next (higher)|| Union of South Africa Queen’s Silver Medal for Bravery (de jure)  |
George Medal (de facto) 
|Next (lower)||Military Medal  |
|Related||Distinguished Service Cross|
The Distinguished Service Medal (DSM) was a military decoration awarded until 1993 to personnel of the Royal Navy and members of the other services, and formerly to personnel of other Commonwealth countries, up to and including the rank of Chief Petty Officer, for bravery and resourcefulness on active service at sea.
The medal was established on 14 October 1914 as the third level decoration for gallantry in action for ratings of the Royal Navy, not at the standard required to receive the Victoria Cross or the Conspicuous Gallantry Medal.  The equivalent decoration for Officers and Warrant Officers was the Distinguished Service Cross (DSC). The DSM ranked below the DSC in order of precedence, between the George Medal and the Military Medal after those medals were established in 1940 and 1916 respectively.  Awards of the DSM were announced in the London Gazette. Recipients are entitled to use the post-nominal letters "DSM".
The DSM was intended to reward bravery at sea. For example, members of the Royal Naval Division, who served alongside the Army in France in the First World War, were eligible for Army decorations, including the Distinguished Conduct Medal and the Military Medal. 
From 1916, ribbon bars could be authorised for subsequent awards of the DSM. 
In 1940 the award was extended to Royal Air Force personnel serving with the Fleet and, in 1942, to members of the Merchant Navy, and Army personnel serving afloat, for example manning a merchant ship's anti-aircraft guns. 
In 1979 eligibility for a number of awards, including the DSM, was extended to permit posthumous awards.  Until that time, only the Victoria Cross and a mention in dispatches could be awarded posthumously.
The Distinguished Service Medal was discontinued in 1993, as part of the review of the British honours system which recommended removing distinctions of rank in respect of awards for bravery. Since then the Distinguished Service Cross, previously only open to Commissioned and Warrant Officers, has been awarded to all ranks. 
The DSM had also been awarded by Commonwealth countries but by the 1990s most, including Canada, Australia and New Zealand, were establishing their own honours systems and no longer recommended British honours. 
The medal was awarded with one of five obverse designs: 
Between 1914 and 1993, approximately 11,311 medals and 227 bars were awarded. 
|Period||Medals||1st bar||2nd bar||3rd bar|
|1914–1919||4,100 [lower-alpha 1]||67||2||–|
|1946–1993||69 [lower-alpha 2]||–||–||–|
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The Distinguished Service Order (DSO) is a military decoration of the United Kingdom, as well as formerly of other parts of the Commonwealth, awarded for meritorious or distinguished service by officers of the armed forces during wartime, typically in actual combat. Since 1993 it has been awarded specifically for 'highly successful command and leadership during active operations', with all ranks being eligible.
The George Medal (GM), instituted on 24 September 1940 by King George VI, is a decoration of the United Kingdom and Commonwealth, awarded for gallantry, typically by civilians, or in circumstances where military honours are not appropriate.
The Distinguished Conduct Medal was a decoration established in 1854 by Queen Victoria for gallantry in the field by other ranks of the British Army. It is the oldest British award for gallantry and was a second level military decoration, ranking below the Victoria Cross, until it was discontinued in 1993 when it was replaced by the Conspicuous Gallantry Cross. The medal was also awarded to non-commissioned military personnel of other Commonwealth Dominions and Colonies.
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The Military Medal (MM) was a military decoration awarded to personnel of the British Army and other arms of the armed forces, and to personnel of other Commonwealth countries, below commissioned rank, for bravery in battle on land. The award was established in 1916, with retrospective application to 1914, and was awarded to other ranks for "acts of gallantry and devotion to duty under fire". The award was discontinued in 1993, when it was replaced by the Military Cross, which was extended to all ranks, while other Commonwealth nations instituted their own award systems in the post war period.
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The Distinguished Flying Medal (DFM) was a military decoration awarded to personnel of the Royal Air Force and other British Armed Forces, and formerly to personnel of other Commonwealth countries, below commissioned rank, for "exceptional valour, courage or devotion to duty whilst flying in active operations against the enemy". The award was discontinued in 1993 when all ranks became eligible for the Distinguished Flying Cross (DFC) as part of the reform of the British honours system.
The Conspicuous Gallantry Medal (CGM) was, until 1993, a British military decoration for gallantry in action for petty officers and seamen of the Royal Navy, including Warrant Officers and other ranks of the Royal Marines. It was formerly awarded to personnel of other Commonwealth countries. In 1943 a Royal Air Force version was created for conspicuous gallantry in action against the enemy in the air.
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