The President of the United States of America, authorized by Act of Congress, July 9, 1918, takes pleasure in presenting the Army Distinguished Service Medal to Major (Armor) Sereno Elmer Brett, United States Army, for exceptionally meritorious and distinguished services to the Government of the United States, in a duty of great responsibility during World War I. As Chief Instructor at Tank Center, American Expeditionary Forces, Major Brett organized and trained the 327th Battalion (Light) Tanks. Later, as Commander of the 326th Battalion (Light) Tanks, he vigorously and skillfully led it in the St. Mihiel offensive over a terrain rendered most difficult through four years of enemy entrenching. Succeeding to the command of the 1st Brigade, Tank Corps, in the Meuse-Argonne offensive, he ably devotedly, and courageously commanded his brigade from 26 September to 10 November 1918; during this period of 46 days his brigade supported eight of the division of the First Army in 18 separate attacks. By his brilliant professional attainments, technical ability, and unusual leadership he contributed in a marked manner to the success of the First Army and rendered most conspicuous services to the American Expeditionary Forces in a position of great responsibility.