The British Forces division of UNIT was initially lead by Brigadier Alistair Gordon "the Brig"  Lethbridge-Stewart (Nicholas Courtney), one of UNIT's founders. His code name: Greyhound One & Jupiter.

The UNIT center of operations is referred to as "Trap One. Soldiers in the field are called "Trap Two." The local police are called "Blue Bottle."

Other UNIT Officers and Personnel included:

Generals

• Angela Bruce as Brigadier Winifred Bambera (Major Husak and Sergeant Zbrigniev reported directly to her)
• David Savile as Brigadier General Chales Crichton (formerly Corporal) who replaced Brigadier Lethbridge-Stewart upon his retirement
• Field-Marshal Thatcher (based in Geneva)

Majors

• John Acheson as Major Beresford
• Chu Omambala as Major Richard Blake (killed by the Sycorax)
• Major Frost, United States officer with an expertise with alien life forms (she was killed - electrocuted - by the Slitheen)
• Paul Tomany as Major Husak (served under Brigadier Bambera)
• Edward Dentith as Major-General Rutlidge, Minstry of Defence officer who supervised Brigadier Lethbridge-Stewart's UNIT operations (forced to killed himself via mind-control)
  Major Walton

Captains

• Richard Franklin as Captain Mike Yates - Code name: Greyhound Three & Venus (brainwashed by the artificial intelligence BOSS and later allowed to retire from UNIT after his involvement with an illegal ecological project designed to reverse time)
• Paul Darrow as Captain Hawkins (killed by the Silurians)
John Breslin as Captain Jimmy Munro, worked with Brigadier Lethbridge-Stewart
• >Robert Sidaway as Captain Jimmy Turner, worked with Brigadier Lethbridge-Stewart

Lieutenants

• Dorota Rae as Flight Lieutenant Françoise Lavel, UNIT helicopter pilot (killed by Morgaine who first stole her memories)
• Lieutenant Richards, served under Brigadier Bambera (killed by the sorceress, Morgaine)
• Surgeon-Lieutenant Harry Sullivan, medical offiicer from the Royal navy attacked to UNIT

  Sergeants
  
  

• John Levene as Sergeant Benton
• Richard Steele as Sergeant Hart (killed by the Silurians)
• Ray Barron as Sergeant Henderson (killed - crushed & turned into compost)
• Alec Linstead as Sergeant Tom Osgood
• Norman Hartley as Flight Sergeant Peters
• Derek Ware as a Sergeant (also played Private Wyatt and Pigbin Jos in later episodes)
Simon Legree as a Sergeant
• James Thornhill as Sergeant Walters
• Robert Jezek as Sergeant Zbrigniev (served under Brigadier Winifred Bambera)

Corporals


• Max Faulkner as Corporal Adams
• Fernanda Marlowe as Corporal Bell Brigadier Lethbridge-Stewart's female administrative adjutant
• James Haswell as Corporal Champion
• Billy Horrigan as UNIT Corporal (also appeared as a guard)
• George Lee as Corporal Forbes (killed by Autons)
• Clinton Morris as a Corporal,
• erek Martin as a Corporal
• Patrick Milner as Corporal
• Bernard G. High a Corporal
• David Savile as Colonel Charles Crichton, (who later replaced Brigadier Lethbridge-Stewart as Brigadier)
• Michael Pinder as Corporal Hopkins
• Corporal Nevin
• Martin Taylor as Corporal Norton
• Alan Mason as Corporal Nutting
• Denys Palmer as Corporal Palmer
• Geoffrey Cheshire as Corporal Tracy

  Privates
  

• Colin Bell as Private Bryson
• Private Harris (wounded during Cyberman invasion)
• Geoffrey Beevers as Private Johnson, (Reegan's henchman)
• David Simeon as Private Latimer
• George Bryson as Private Ogden
• James Clayton as Private Parker
• Stacy Davies as Private Perkins (killed during the Cybermen invasion)
• Harry Swift as Private Robins (he tted suicide -jumped into a chasm)
• Private Upton (died fighting the Silurians)
• Derek Pollitt as Private Wright (killed by the Silurians)
• Derek Ware as Private Wyatt (he died in a fall - also played Pigfin Josh)
Soldiers
• Grimshaw, UNIT soldier (saved by Sarah Jane Smith.)
• Max Faulkner as a UNIT soldier (also played Corporal Adams)
• Les Conrad as a UNIT soldier (also played a UNIT officer)
• Pat Gorman as a soldier (also appeared as a UNIT Corporal)
• Brian Fellows as a soldier
• Peter Symonds as a soldier

Guards


• David Melbourne, as a UNIT Guard
• Terry Walsh as a UNIT Guard
• Billie Horriganas a UNIT Guard
• Brian Justice as a UNIT Guard
• Alan Chuntz as a UNIT Guard
• John Scott Martin as a UNIT Guard
• David Masterman as a UNIT Guard
• Harry Fielder as a UNIT Guard
• Ian Elliot as a UNIT Guard

UNIT Technicians & Personnel



• Anita Briem as Sally Jacobs, a technician on duty in the UNIT Tower of London faciity during the Sycorax invasion
• Ellis Jones as a UNIT Technician
• Iain Smith as UNIT personnel
• Tessa Shaw as UNIT personnel
• Leon Maybank as UNIT personnel
• Barbara Chambers as UNIT personnel
  
  Civilians
  
  

• Mr Campbell, a Scotsman working in UNIT's scientific supply section
• Michael Ely as a Chauffeur
• Peter Bathurst as Horatio Chinn, worked the Ministry of Defence with responsibilities for Homeland Security tasked with supervising UNIT.
• Paul Grist as Bill Filer, an American intelligence agent sent to work with UNIT
• Freema Agyeman as Dr. Martha Jones, the Companion to the tenth Doctor and medical officer for UNIT and assisted agents from Torchwood
• Angela Douglas as Doris Lethbridge-Stewart, worked for UNIT alongside Brigadier Lethbridge-Stewartm, her husband (both like to garden)
• Gypsie Kemp, as UNIT Radio Operator
• Caroline John, Liz Shaw as assistant to Scientific Advisor (The Third Doctor)
• Elisabeth Sladen as Sarah Jane Smith (Companion to Third and Fourth Doctor and later an investigative journalist on her own spinoff series)
• Sir John Sudbury. a high-ranking British civil servant with C19
  Katy Manning as Josephine "Jo" Grant, (temporary Assistant to UNIT Scientific Advisor and companion to the Third Doctor)

Miscellaneous Officers

• Les Clark as UNIT officer Gordon Stothard
• Bill Matthews as UNIT officer
• Barry Wade as UNIT officer
• Dave Carter as UNIT officer
• Martin Gordon as UNIT officer
• Leslie Weekes as UNIT officer
• Tony Jenkins as UNIT officer
• Les Conrad as UNIT officer
• Richard Atherton as UNIT officer

By the end of the original series, UNIT had amassed an arsenal of anti-alien weaponry: silver bullets, Teflon anti-Dalek shell, high explosives for Yeti, armor piercing for robots, and gold tipped explosives for battling the Cybermen.

UNIT returned when the new DOCTOR WHO re-launched  successfully on the BBC in 2005. See also "Torchwood"