The Chief of Operations is a position normally found only on Starbases and other static installations. This position combines the roles of Chief Engineering Officer and Operations Officer, and occasionally spans into the role of Quartermaster.
As with the Chief Engineering Officer, the Chief of Operations is responsible for all engineering aspects of the station, and is responsible for the operations, repair, and maintenance of the station itself. In addition, the CoO is responsible for effecting repairs on any damaged ships that visit the station.
The most well-known CoO was Senior Chief Petty Officer Miles O'brien, who served in that capacity on Deep Space Nine for almost seven years. During this time, he was responsible for the upgrades to the station itself, as well as repairing and upgrading the USS Defiant. Additionally, he was in charge of coordinating all repair efforts at DS9 during the Dominion War.