Department head

A department head was an officer who headed or represented a particular department aboard a starship that made up one of many links in the chain of command leading up to the senior staff.

Department heads had several duties, including personnel assignments and personnel matters, and preparing reports, including damage reports, for staff meetings. They also coordinated directly with the first officer for systems allocation and personnel transfers, among other things. 

According to Lieutenant Commander Nella Daren, who was head of stellar sciences aboard the USS Enterprise (NCC-1701-D) in 2369, the role of "any good department head" was to make the effort of "trying to build the best staff I can," and be most effective. 

During the early 2260s, it was not uncommon aboard the USS Enterprise (NCC-1701) to have James T. Kirk request that his department heads meet on the bridge to deliver reports of readiness or recommendations for the current situation. 

When Captain Edward Jellico took command of the Enterprise-D in 2368, he requested that his XO Commander William T. Riker to change the ship's watch rotation to a four shift rotation, along with readiness reports from each department head by 1400 hours and a meeting with the senior staff at 1500. However, when Jellico later checked up on the progress of his requests, he found that Riker had not yet implemented the four shift rotation, and that, according to Riker, "I have spoken to the department heads about changing from three shifts to four, and they assure me it's going to cause us significant personnel problems." Jellico then ordered Riker to "tell the department heads that as of now the Enterprise is on a four shift rotation."

After Commander Riker worked out the new rotation schedules, in 2369, he asked if Data would cross-check it with personnel assignments, and notify the department heads of the new changes. 

In 2373, when Voyager encountered a class 17 nebula composed sirillium, Captain Janeway requested to have "all the department heads submit proposals for sirillium usage."

In the case of arrangement aboard USS Voyager, while stranded in the Delta Quadrant, security chief Tuvok had thirteen department heads who reported to him every day in 2374.