Chief medical officer

The chief medical officer is an officer who is directly in charge of a starship's sickbay or infirmary on a starbase. This officer is in charge of all medical personnel at the facility and oversees the health of the crew.

The CMO also has the power to relieve their commanding officer regardless of the CMO's rank if they judge the CO of been unfit for duty. 

In Star Trek: Confederation, chief medical officers are called Chief Medical Commanders and can be promoted to Rear Admiral and Admiral for their respective positions of Deputy Director and Director of Science/Medicine (Star Trek: Confederation: "Williams One")

Notable Chief Medical Officers

 * Tabatha Brisk
 * UFS
 * Matthew Donahugh
 * USS (2377-2381)
 * USS (2383-)
 * Christine Holley
 * USS
 * Lox
 * USS
 * Valerie Lupia
 * USS (2289-2294)
 * USS (2295-)
 * Carol Murphy
 * USS
 * Atana Ral
 * USS (2378-2396)
 * Orlando Sturges
 * USS (2383-)
 * The Doctor
 * (Federation Starfleet} USS (2371-2377)
 * (Copy; Confederation of Earth) HMS (Late 2380-Present)