|Known Lieutenant||Known Lieutenants|
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Lieutenant is the last line officer rank deemed to be a 'junior officer', ranking above Lieutenant JG and below a Lieutenant Commander. It has a ranking code of O-3 and is equivalent to a Captain in the Starfleet Marine Corps. The rank insignia consists of two full pips.
Lieutenants are most commonly billeted as Department Heads aboard a starship or starbase. Occasionally, in lieu of a more senior officer, a Lieutenant may temporarily command a small starship, though this is rare and usually only done in emergency circumstances. Often, a Lieutenant may hold command of a team within a department - a security detail, or engineering team, for example.