In Imperial Service Edit
Unlike Colonel, a Lieutenant Colonel primarily served in the field, though they sometimes served as a staff officer advisor or assistant to a higher ranking officer. A Lieutenant Colonel was equivalent to a Commander in the Imperial Navy.
In New Republic Service Edit
A Lieutenant Colonel in the New Republic Army was often the chief supporting officer to the Colonel, serving as a bridge between the base and the field. In the New Republic Marine Corps, a Lieutenant Colonel was assigned to a starship and put in charge of an entire vessel's Marine Force Contingent or their own Batallion. Other roles included being a direct aide to the flagship General, or perforing the roles of a Major. Support officers of thsi rank were typically assigned on a Brigade Level, capable of commanding an entire starship's detachment of support personnel. Lieutenant Colonels were the highest ranked field combat commanders.
In the New Republic Starfighter Corps, these men were assigned to a starship and put in charge of an entire vessel's Strike Force, or in charge of their own squadron. They could serve as direct aides to the flagship General, or perform the roles of a Major. Support officers of this rank were typically assigned on a Strike Group level, capable of commanding an entire starship's detachment of support personnel.
In Union Service Edit
Use of the Lieutenant Colonel rank in Union Marines and Provincial Army circles was typically applied to aides and secondary officers of regiment-commanding Colonels. A Lieutenant Colonel was often the regiment's executive officer, and perhaps led a regiment if the regiment in question was a support unit or a newly-trained unit. The Marines frequently used Lieutenant Colonels for Marine attachments on large, independently-operating warships such as battlecruisers and battleships where a full regiment was not quite necessary. Majors were also used for this role, but typically on smaller warships — cruiser and below.
Of special note, the promotion to Lieutenant Colonel was often looked upon as the "kiss of boredom" in the Marine Aerospace Division, as this rank, and the responsibilities associated with it, often took the Madman out of the fighter cockpit and put them into an office or flight director's chair. Lieutenant Colonels in the MAD were often linked to a Marine Colonel as part of their support staff so as to coordinate MAD activity; this was done from a command post or, at the very least, from the cockpit of a L-202 Hellhawk. For this reason, fellow Madmen used to nickname Lieutenant Colonels as "Liftenant Colonels" or "Lifter Looies".
By tradition, the rank was pronounced leftenant colonel.