Lieutenant Commander

From Obsidian Fleet Database

Lieutenant Commander Affiliation Starfleet Higher Rank Commander Lower Rank Lieutenant
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Lieutenant Commander (Abbreviated to LtCdr) is the lowest senior line officer rank, above Lieutenant and below Commander. Lieutenant Commanders generally serve as department heads on large starships and starbases. They may be the executive officer or possibly commanding officer of a ship or facility, but this is rare.

Starfleet Officer Ranks
Ensign	Lieutenant JG	Lieutenant	Lieutenant Commander	Commander	Captain	Commodore	Rear Admiral	Vice Admiral	Admiral
For the Starfleet Warrant Officer rank structure click here
For the Starfleet Enlisted rank structure click here