The Merchant Marine Meritorious Service Medal is a decoration of the United States Merchant Marine. It is awarded to any seamen of any ship operated by or for the War Shipping Administration who is commended by the Administrator for conduct or service of a meritorious nature, but not sufficient to warrant the Merchant Marine Distinguished Service Medal. Regulations state that not more than one medal shall be issued to any one seaman, but for each succeeding instance sufficient to justify the award of a medal, there will be awarded a suitable insignia to be worn with the medal.