Regimental Sergeant-Major (abbrev: RSM) is an enlisted paygrade within the Royal Manticoran Marine Corps and the Royal Manticoran Army. It holds the equivalent military paygrade of E-10 within The Royal Manticoran Navy: The Official Honor Harrington Fan Association, Inc. and is often the right hand of the supervising officer. Becoming the most senior non-commissioned officer (without a warrant, they are often part of the leadership triad (commanding officer, executive officer, senior NCO). A soldier who has received their third rocker is generally referred to as "Sergeant-Major," never just "Sergeant."
In peacetime, a regimental sergeant-major will have served a minimum of 12 years in the service, but there is no Time in Grade requirement. Instead, promotions are handled by an enlisted review board at Admiralty House or Royal Army Headquarters because of the trust and responsibility that are required of the holder of this rank. The Royal Manticoran Army uniform is green with yellow stripes bordered by blue. The Royal Manticoran Marine Corps is black with yellow stripes bordered by green.
If the soldier has completed their Regimental Sergeant-Major Exam, with 24 months Time in Grade, they qualify for this rank. However, they need to be approved before the Enlisted Review Board before they earn that rank.  Regimental Sergeants-Major can hold the position of Gunny in a MarDet, but usually are in more executive positions.
- E-10 equivalents from other branches of The Royal Manticoran Navy: The Official Honor Harrington Fan Association, Inc.:
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-  (Membership Handbook)