A dockmaster is a person who is responsible for the docking procedures of an outpost.
In 2151, an alien dockmaster informed Captain Jonathan Archer and Subcommander T'Pol that a Klingon K'toch class scoutship had visited his trade outpost on Rigel X seven days beforehand. While in his control tower, the alien dockmaster monitored the approach vector of Elkan Nine. (ENT: "Broken Bow")
In 2154, Captain Erika Hernandez of the Template:ShipClass starship Columbia requested clearance to depart from the dockmaster of Starfleet's drydock. (ENT: "Affliction")
In 2293, Captain James T. Kirk asked Commander Uhura to hail the dockmaster, so the USS Enterprise-A could depart from spacedock. (Star Trek VI: The Undiscovered Country)
A dockmaster aboard Deep Space 9 had an office on the Promenade. (Star Trek: Deep Space Nine set decoration)