During the Dominion War, Starfleet ships were divided into fleets. Some of these fleets included Klingon and Romulan forces as well.
Second Fleet
At the time of its inception, the Second Fleet was a fleet comprised of Galaxy-class, Defiant-class Miranda-class, Excelsior-class, Sabre-class, Akira-class and Steamrunner-class Federation starships, as well as Vor'cha-class, K'Vort-class, and K't'inga-class Klingon starships.
During the second Battle of Deep Space 9, in late 2373, the Second Fleet crossed the border into Cardassian space and destroyed the Dominion shipyards on Torros III. The fleet was later joined by the USS Defiant and IKS Rotarran following the evacuation of Deep Space 9. (DS9: "Call to Arms", "A Time to Stand")
Later in 2374, the fleet was pulled out of the Kotanka system to be part of the task force sent to retake Deep Space 9 (see Operation Return). (DS9: "Favor the Bold", "Sacrifice of Angels")
The fleet was later sent in an offensive against the Dominion forces occupying Betazed. (DS9: "The Sound of Her Voice")
Third Fleet
This fleet remained to protect Earth when the Second and Fifth Fleets participated in the retaking of Deep Space 9 in 2374. Later in the war, the fleet requested two more Romulan attack wings.
Fifth Fleet
This fleet fought along the Vulcan border, until it joined the task force sent to retake Deep Space 9. (DS9: "Favor the Bold")
Sixth Fleet
This fleet was pulled from the Bolian front in 2375. (DS9: "Penumbra")
Seventh Fleet
This fleet attempted to stop the Jem'Hadar in the Tyra system in 2374, but only 14 ships survived of the 112 in the fleet. The Seventh Fleet later took heavy losses again, this time at Sybaron, and it was still at half strength when sent to try to cut off the Dominion at the Tibor Nebula. In 2375, the fleet was assigned to launch an offensive in the Kalandra sector.
Vessels assigned to the Seventh Fleet included USS Destiny.
Ninth Fleet
The fleet was intended to be used in the effort to retake Deep Space 9 but did not arrive in time. Deep Space 9 was later designated as headquarters to this fleet and General Martok was made its Supreme Commander.
Vessels assigned to the Ninth Fleet included USS Akagi, USS Exeter, USS Potemkin, USS Sutherland and IKS Rotarran (General Martok's flagship while he was Supreme Commander of the Ninth Fleet)
- DS9:
- "Favor the Bold"
- "You Are Cordially Invited..."
- "Change of Heart"
- "Once More Unto the Breach"
Tenth Fleet
This fleet was assigned to protect Betazed and its colonies, but while the fleet was on a training exercise, the planet fell to the Dominion. (DS9: "In the Pale Moonlight")