UNIT

The Unified Intelligence Taskforce — formerly known as the United Nations Intelligence Taskforce, alternately as the United Intelligence Taskforce, (AUDIO: The Dalek Transaction) and more usually called UNIT — was a military organisation which operated under the auspices of the United Nations. Its remit was to investigate and combat paranormal and extraterrestrial threats to the Earth. UNIT was not the only alien defence organisation, but it was the one with which the Doctor had the closest personal involvement.

Roots and predecessors
An early 20th century counterpart to UNIT was LONGBOW. This world security organisation was set up by the UN precursor, the. LONGBOW dealt with the occasional extraterrestrial incident, but was disbanded after the League and it failed to prevent World War II. (PROSE: Just War)

The roots of UNIT itself, however, lay in later alien encounters. The Intrusion Countermeasures Group headed by Group Captain Ian Gilmore, which got involved in the Shoreditch Incident, served as a specialised military force with scientific assistance would seem almost a trial run for UNIT, though not an international organisation. Though Gilmore did have two scientific advisors serving much as the third incarnation of the Doctor and Dr Elizabeth "Liz" Shaw would later, the seventh incarnation of the Doctor did most of the work on the technical end. (TV: Remembrance of the Daleks, PROSE: Who Killed Kennedy)

An incident which led directly to the creation of UNIT was the takeover of London by the Great Intelligence, with robot Yetis and a deadly cobweb-like fungus. Assisted by the Second Doctor, another group of British infantrymen, led by then-Colonel Alistair Gordon Lethbridge-Stewart, beat back the Yeti from the tunnels of the London Underground. (TV: The Web of Fear)

Formation
The United Nations were aware the world faced threats from extraterrestrial sources. As space programmes sent probes deeper and deeper into space, mankind was drawing attention to itself. (TV: Spearhead from Space) Unable to get the British government to form a permanent special operations force for alien threats, Lethbridge-Stewart went over their heads to the UN Security Council, who proved more receptive. (PROSE: Who Killed Kennedy) The UN established UNIT with the mandate to investigate, monitor and combat such threats. At the suggestion of Gilmore from the ICMG, (PROSE: The Scales of Injustice) Lethbridge-Stewart was promoted to the rank of Brigadier and put in charge of the British contingent. (TV: The Invasion) This contingent was organisationally known as Department C19 within the British government.

Alistair Gordon Lethbridge-Stewart
One of UNIT's first missions was an intensive investigation of International Electromatics, which turned violent. UNIT agents were killed and UNIT launched a helicopter raid to liberate prisoners at an Electromatics' facility. With the help, again, of the Second Doctor, UNIT discovered the company was a front for a Cybermen invasion, and was able to defend against it. (TV: The Invasion)

Lethbridge-Stewart became convinced of the necessity of scientific advice in battling extraterrestrial threats. He recruited Liz Shaw from the University of Cambridge. Around that same time, the Third Doctor had been exiled to Earth by the Time Lords. He agreed to join UNIT as its scientific advisor just in time to help defeat the Nestene Consciousness' invasion of Earth using its Autons in an attack on the Auto Plastics factory. (TV: Spearhead from Space)

The Doctor continued to assist UNIT. In Wenley Moor, UNIT soldiers guarded the cave entrances to prevent the Silurians from getting out. Against the Doctor's wishes, the Brigadier ordered Corporal Nutting to blow up the Silurian base beneath Wenley Moor, permanently sealing the base off. (TV: Doctor Who and the Silurians) While the third and eleventh incarnations of the Doctor stated in some accounts that this tribe had all died, (TV: Doctor Who and the Silurians, Cold Blood) according to another account, the Third Doctor said they were only entombed. (PROSE: The Scales of Injustice) UNIT also encountered the Primords. (TV: Inferno)

UNIT troops led by Sergeant Benton successfully fought off a fleet of Silurians on the Kent coast, while troops led by the Brigadier rescued the Doctor and Sergeant Mike Yates from a splinter group of C19 in Northumberland. After this, Liz Shaw left UNIT. (PROSE: The Scales of Injustice)

The Doctor gained a new assistant in Jo Grant. Not a scientist, Jo had only managed to take science up to A level, of which she later stated, "I never said I passed". As Jo began assisting the Doctor, UNIT met and made an enemy out of another Time Lord —. (TV: Terror of the Autons) UNIT eventually caught and imprisoned him after several attempts to destroy Earth. (TV: The Dæmons)

When the Doctor's exile was ended, (TV: The Three Doctors) his association with UNIT became more sporadic, especially after his regeneration into his fourth incarnation. (TV: Planet of the Spiders, Robot, Pyramids of Mars)

The Doctor did return to Earth with Sarah Jane Smith, but would work less with the Brigadier and more with such other officers as Colonel Faraday (the Brigadier having gone to Geneva) (TV: The Android Invasion) and Major Beresford. (TV: The Seeds of Doom) The Doctor, however, never officially left UNIT. (TV: The Sontaran Stratagem)

As a United Nations group, UNIT often served as security at peace conferences, (TV: Day of the Daleks, The Mind of Evil) and the British contingent had foreign soldiers such as Sergeant Zbrigniev. (TV: Battlefield)

UNIT often faced hostility to its operations when investigating research facilities and companies. A common tactic against them was an appeal to any contacts in the Westminster government. These forced Lethbridge-Stewart either to back down or go over the government's heads to Geneva. (TV: The Invasion, The Green Death, The Claws of Axos)

After Lethbridge-Stewart
Lethbridge-Stewart retired in 1976 to teach mathematics at Brendon Public School. His successor was Colonel Charles Crichton. (TV: The Five Doctors) Benton and medical officer Harry Sullivan also left. (TV: Mawdryn Undead)

Colonel Lafayette was briefly in charge of UNIT, before being killed by the Skyheads. He was replaced by Wyland-Jones. (AUDIO: Dominion)

In the 1990s, Iris Wildthyme worked part-time as UNIT's special scientific advisor. (PROSE: Interference - Book Two, Bullet Time)

In 1997, the Doctor re-united with UNIT in his seventh incarnation against an invasion by Morgaine and her armoured knights. The British contingent was commanded by a new, female brigadier Winifred Bambera. Lethbridge-Stewart was called out of retirement to assist them. (TV: Battlefield)

The Seventh Doctor would help UNIT officer Muriel Frost in the late 1990s in their struggle against the Mandragora Helix. (COMIC: The Mark of Mandragora, Evening's Empire)

At some point in the late 20th or early 21st century, Sarah Jane Smith published the book UNIT Fighting for Humankind about the history of UNIT. (TV: Whatever Happened to Sarah Jane?)

General trends
In the name of "homeworld security", UNIT adopted a controversial attitude towards and  which the Tenth Doctor found disquieting. (TV: The Sontaran Stratagem) UNIT maintained a secret prison. Detainees could be held without charges being pressed or without the usual rights of prisoners. This suggested UNIT had a more malevolent side than other recorded encounters may suggest. Among those kept at one time as a prisoner by UNIT was Toshiko Sato in 2005 or 2006; she was only released when Jack Harkness and Torchwood Three convinced her to work for them. (TV: Fragments)

In the late 20th and early 21st centuries, UNIT maintained a small division based in the United States, led by Brigadier General Adrienne Kramer. (PROSE: Vampire Science)

At sometime prior to the 2009 Sontaran invasion, UNIT changed its name from United Nations Intelligence Taskforce to Unified Intelligence Taskforce. UNIT retained its traditional logos, even though they displayed the now-technically incorrect initialization "U.N.I.T." (TV: The Sontaran Stratagem)

Specific events
At some point, the UK division of UNIT faced being shut down and replaced with domestic group ICIS (Internal Counter-Intelligence Service). When it became clear ICIS were brutal and dangerous, Lethbridge-Stewart and Colonel Emily Chaudhry deliberately revealed UNIT's remit to the press (stating UNIT had faced over two hundred invasions) and the existence of Silurian ambassadors. This was viewed as a hoax, but it forced the government to leave UNIT in charge of alien matters, leading to uneasy co-existence with ICIS. (AUDIO: The Coup)

Unknown to UNIT, their leader, Colonel Brimmicombe-Wood, was an ICIS plant who had been groomed to assume leadership of their rival. (AUDIO: The Wasting) ICIS' involvement in an attempted coup (AUDIO: The Longest Night) and murderous attempts at framing UNIT led to their shutdown; UNIT thwarted the coup and stopped a worldwide pandemic, unfortunately losing temporary commander Colonel Robert Dalton in the process. Colonel Chaudry was given command of the UK contingent. (AUDIO: The Wasting) The position was later handed to Colonel Mace under unknown circumstances

In 2006, UNIT sent a delegation to a gathering of experts to 10 Downing Street in response to a spaceship crash in the River Thames. All of the experts were electrocuted by the Slitheen family. (TV: Aliens of London) By this time, UNIT and the Torchwood Institute were aware of each other. (TV: Fragments) UNIT asked for the assistance of Torchwood Three's Owen Harper while the crashed ship's apparent pilot, dubbed the Space Pig, was taken to Albion Hospital. Toshiko Sato filled in for Owen for the assignment. (TV: Aliens of London, Exit Wounds)

In 2006, a group of at least three Groske were stranded on Earth. UNIT found and recruited them. (TV: Death of the Doctor)

In Christmas 2006, UNIT had a command centre in the Tower of London under the command of Major Blake. (TV: The Christmas Invasion) UNIT maintained contact with Torchwood Three, even after the Battle of Canary Wharf. Torchwood Three's leader, Jack Harkness, would occasionally confer with the heads of UNIT and once asked for and received the help of Martha Jones, a medical doctor and former companion of the Tenth Doctor's, whom he and the Doctor had suggested for a position with UNIT. (TV: Reset)

By 2008, UNIT operated an aircraft carrier airship, the Valiant, which was mainly designed by British Minister of Defence Harold Saxon, who was in fact. (TV: The Sound of Drums / Last of the Time Lords)

In early 2008, when the Cardiff Space-Time Rift fractured resulting in time slips across the world, UNIT was one of several organisations that noticed the strange appearances that were occurring worldwide and asked if it had anything to do with Torchwood. (TV: End of Days)

Sarah Jane Smith remained in friendly contact with UNIT, leading to its involvement in cleaning up a Slitheen plot. (TV: Revenge of the Slitheen) Her status as one of the Doctor's companions during his time as their Scientific Advisor seemed to have given her some pull; Sarah Jane said mentioning her name would ensure good pay. (TV: The Man Who Never Was)

Prior to the 2009 Sontaran invasion, Martha Jones, an ex-companion of the Tenth Doctor was tasked with alerting him about it when the preparations for the invasion were discovered. (TV: The Sontaran Stratagem) Apparently, now-Sir Alistair Lethbridge-Stewart still had some involvement with UNIT at this time, though he had gone to Peru for undisclosed reasons. (TV: The Poison Sky)

Following the defeat of the Sontarans, UNIT began reverse-engineering technology scavenged from the aliens, and launched Project Indigo to create a backpack-sized teleportation device. Jones was seconded as medical advisor for the project (it was top secret, although Harkness found out about it), and stationed at UNIT's base in New York City. (TV: The Stolen Earth) UNIT also developed a contingency plan called the Osterhagen Project; in the event of global conquest that seemed unending, any three out of five UNIT facilities would end humanity's suffering by destroying the planet with nuclear weaponry under Earth's crust. (TV: Journey's End)

Following the relocation of the Earth and 26 other planets to the Medusa Cascade, UNIT went on high alert, and then a war footing as the Dalek invasion began. Both the Valiant and the New York headquarters were overrun by Daleks and destroyed, and the United Nations surrendered soon after. Martha Jones escaped using the Project Indigo device, maintaining possession of an Osterhagen key in the process. (TV: The Stolen Earth) She reached the Osterhagen Station in Germany. The Chinese and Liberian stations had been already activated. She was teleported away by the Daleks before the bombs could be triggered. The Doctor later asked her to have the Project dismantled. (TV: Journey's End)

UNIT and Torchwood made a joint effort to investigate the voices coming from the Mariana Trench. UNIT supplied the submarine, the Octopus Rock, and the ship to transport it, the USS Calvin. (AUDIO: Submission)

During Easter 2009 UNIT was called out to a tunnel near Brixton after a bus carrying the Tenth Doctor and other passengers had gone through a wormhole. The Doctor contacted the senior officer on site, Captain Erisa Magambo and also spoke with their scientific adviser Professor Malcolm Taylor. He managed to get the bus back to its original location but the Swarm arrived on Earth. Magambo and UNIT fought the stingrays. The Doctor recommended to Magambo that there might be two more potential UNIT recruits from the bus, namely Barclay and Nathan. (TV: Planet of the Dead)

In September 2009, UNIT investigated when every child in the world stopped, which was a prelude to the return of the 456. Colonel Augustus Oduya met with civil servant John Frobisher and showed him locations of children who had stopped all over the world, announcing his suspicions of an alien invasion. He correctly deduced that if UNIT had pieced the situation together, then Torchwood Three also must have. (TV: Children of Earth: Day One) Arriving at Downing Street to witness the 456's first contact, Oduya wanted UNIT to be involved in the handling the incident. (TV: Children of Earth: Day Three) After Frobisher killed himself, Colonel Oduya was selected to continue negotiations with the 456, and UNIT soldiers entered Floor 13. Oduya asked — not as a representative but as a father — what the 456 would do to the children once they were handed over. Upon receiving the reply that the children would essentially be used for drugs, he was clearly horrified. Oduya was present when the the 456 Ambassador was killed due to the actions of Jack Harkness which saved the Earth. (TV: Children of Earth: Day Five)

When the Master turned every human into a copy of him on Christmas Day 2009, UNIT came under his command. When the Tenth Doctor piloted the Hesperus to Joshua Naismith's mansion  the following morning, the Master Race-controlled UNIT fired missiles at the Doctor. Wilfred Mott and Rossiter the Vinvocci destroyed them. When Rassilon and his Time Lord guard arrived at the mansion, his first act was to reverse the Master race back to their human forms. (TV: The End of Time)

2010s
On 4 May 2010, after the Eleventh Doctor had destroyed an awaking Cyberman army, he predicted that a lot of questions would be asked by UNIT. He advised Chisholm to simply mention his name. (GAME: Blood of the Cybermen)

In 2010 the Skith attacked a UNIT base at the bottom of the sea near Sydney. (COMIC: The Age of Ice)

Later that year, rogue Colonel Tia Karim leagued with Claw Shansheeth to gain the Doctor's TARDIS. They created a ruse that the Eleventh Doctor had died and prepared his funeral in UNIT Base 5 so they could drain the life force of Sarah Jane Smith and Josephine Jones through their memories of the Doctor. They attached them to the memory weave and began the process to conjure a TARDIS key. The machine was overloaded by the many memories of Jo and Sarah Jane and it self-destructed, killing the group. (TV: Death of the Doctor)

In 2011, after the Miracle Day phenomenon was negated, UNIT sealed off the Blessing. (TV: The Blood Line)

After Kate Stewart became head of scientific research, UNIT took in Shakri cubes and experimented on them; they subjected them to temperatures from -200 to 200 degrees Celsius, simulated a water depth of five miles, dropped one out of a helicopter at 10,000 feet and rolled UNIT's best tank on one. The cubes were left intact. A year later, when the cubes activated and behaved unusually, several dozen were contained and examined in the Tower of London. Stewart called in the Eleventh Doctor and Amy Pond on the Doctor's psychic paper to look into this. (TV: The Power of Three)

In 2013, after the minds intended for the Great Intelligence were downloaded back into their bodies, UNIT took control of the Shard in London. They saw the workers' "factory settings" from before the Intelligence took over restored, causing them to forget their work. (TV: The Bells of Saint John)

Later in 2013, after figures from the Under-Gallery's stasis cube paintings had disappeared along with the glass of the paintings being smashed outwards, UNIT summoned the Eleventh Doctor under the instructions of Queen Elizabeth I from the 16th century. The figures in the paintings were actually Zygons who hid themselves inside in 1562 while waiting for the Earth to become more suitable for invasion. UNIT had accidentally airlifted the TARDIS to the National Gallery not knowing the Doctor was still inside. The Zygons later took on the biological forms of Kate and UNIT scientists McGillop and Osgood and tried taking over the Black Archive. Trying to stop them, Kate set off the countdown for a nuclear warhead, which her duplicate was unable to cancel, but the Tenth, Eleventh and War Doctors broke into the Black Archive, erasing the minds of the Zygons and the real Kate, McGillop and Osgood and making them forget which was "real" and allowing both Kates to agree to cancel the detonation. The Doctors refused to return the memories of the two parties until they agreed to a peace treaty. (TV: The Day of the Doctor) Twenty million Zygons were resettled in human form among the humans worldwide as part of Operation Double, a covert operation outside of UNIT's normal strictures. (TV: The Zygon Invasion)

In 2014, all UNIT troops were occupied with spiked headed robots that were emerging from the eruption at the El Hierro volcano. (PROSE: The Crawling Terror)

In 2014, prior to the month of August, UNIT assembled outside of the House of Commons to disintegrate a Kharitite that was feeding on the negative emotions inside the building and destroying it in the process. They threatened to disintegrate Alice Obiefune if she did not agree to step out of their line of fire, but the Eleventh Doctor arrived in time to stop them. When a walking squid exited the TARDIS, they initially believed the squid had either taken over the TARDIS or that the Doctor had regenerated into the creature. They planned to fire at it even if it was the Doctor. (COMIC: After Life)

In late 2014, UNIT helped the Twelfth Doctor and Clara Oswald defeat the Fractures. (COMIC: The Fractures)

Shortly afterwards, UNIT investigated 3W, (TV: Death in Heaven) an organisation set up by one Dr Skarosa to create a place to house the consciousness of the deceased. Meanwhile, the Twelfth Doctor and Clara discovered 3W while searching for the recently deceased Danny Pink, and learnt the organisation's true nature as an operation manipulated by, who used a Matrix data slice to create the Nethersphere where the minds of the recently deceased would be uploaded and converted into an army of Cybermen. When the Cybermen emerged from 3W's base in St Paul's Cathedral, (TV: Dark Water) UNIT soon arrived on the scene led by Kate Stewart. Capturing both the Doctor and the Master, UNIT brought the two Time Lords aboard their presidential aircraft, Boat One, where the Doctor was met by Colonel Ahmed and inaugurated as an emergency President of Earth. At this time, clouds appeared over the world's major cities, raining cyber-pollen on the graveyards to convert the dead into Cybermen. These Cybermen, now possessing the ability to fly, attacked Boat One resulting in its destruction with all hands including Colonel Ahmed and Osgood with the Doctor and the Master escaping. Offered control of the Cybermen army by the Master, the Doctor refused to submit to her claim that he was like her, he handed it over to Danny Pink, who rallied all the Cybermen to self-destruct, taking the pollen clouds with them. However, one Cyberman remained, converted from the late Brigadier Lethbridge-Stewart. Having rescued his daughter from the destruction of Boat One, he returned to the graveyard where he saved the Doctor the obligation of killing the Master. Receiving his wish of a salute from the Doctor, the Brigadier flew off. (TV: Death in Heaven)

During the month when the Hyperions ruled Earth in the summer of 2015, UNIT became a small resistance group led by Kate Stewart. The Twelfth Doctor provided them with alien weaponry to fight back against the Hyperions in London. (COMIC: The Hyperion Empire)

Missy, having survived the Brigadier's blast, grabbed UNIT's attention by using a time stop to freeze every plane in the sky across the globe, so that she could discuss the Doctor's confession dial with Clara, with eight snipers sent to ensure Clara felt safe enough to talk to her. Later, UNIT's scientists used a computer algorithm to find anachronisms and "crisis points" revealing the location and time period of the Doctor's meditation on Earth prior to his demise. Missy then used her vortex manipulator to bring Clara to 1138 Essex. (TV: The Magician's Apprentice)

UNIT's forces in the UK, along with a platoon in Turmezistan, were all killed by a radicalised faction of Zygons called Truth or Consequences after the peace treaty between humans and Zygons began breaking down. (TV: The Zygon Invasion) The ceasefire was later put back in place. (TV: The Zygon Inversion)

Mayor Me considered her hidden trap street, which had existed in London for at least a century prior to Operation Double, to be a more favourable way of housing aliens on Earth as opposed to the settling of the Zygons amongst humanity. Later, in a desperate gambit to prevent Clara Oswald from sacrificing herself, the Twelfth Doctor threatened Me to relinquish the Quantum Shade on Clara or he would expose her trap street and bring UNIT and the Zygons down on it. (TV: Face the Raven)

In 2016, UNIT cleaned up the mess left by the Transhuman Sisters of the Unholy Plentitude after they tried to kill. (AUDIO: And You Will Obey Me)

In 2016, a UNIT team was brought in to take away Garry Fletcher's alien body-swapping technology. (PROSE: Joyride)

Andrea Quill was aware of UNIT and asked Dorothea Ames if she was affiliated with them. Dorothea replied that who she represented were "far more modest than that." (TV: Brave-ish Heart)

After foiling the Shoal of the Winter Harmony's plot to take over Earth using the corporation Harmony Shoal as a front, the Twelfth Doctor tipped UNIT off to their existence. Refusing to accept defeat, however, Harmony Shoal vowed revenge and secretly infiltrated the UNIT team sent to close their head office in New York. (TV: The Return of Doctor Mysterio)

2040s
By 2040, UNIT was a shadow of its former self. (PROSE: The Baron Wastes)

Beyond the 21st century
UNIT still existed in 2119. Alice O'Donnell was a fan of their work, and was familiar with the Doctor's association with the group, and Mason Bennett wanted to work for them. (TV: Under the Lake) The Doctor still had ties with them, and the Twelfth Doctor assured Clara Oswald that they would cut out the Faraday cage from the Drum and take it into space. (TV: Before the Flood)

Following human expansion into the galaxy, UNIT evolved into the Foreign Hazard Duty. (COMIC: The Mark of Mandragora, Echoes of the Mogor!)

By the 26th century, UNIT had become a secret society called the Unitatus. (PROSE: Cold Fusion) Unitatus survived at least until the 30th century. (PROSE: So Vile a Sin)

United Galactic Intelligence Taskforce (UGIT) was another of UNIT's successor organisations. (AUDIO: Council of War)

Headquarters and command centres
UNIT had a command centre in the cargo hold of a C-130 Hercules military transport aircraft and could use the plane itself as a mobile base. (TV: The Invasion)

The British branch of UNIT later operated out of an office building in London (TV: Spearhead from Space). It also maintained a mobile headquarters in the form of a large bus-like vehicle that could be driven to the site of an incident. (TV: The Dæmons) The HQ subsequently moved a number of times, finally settling in a building in the country that had been built over the ruins of a priory. (TV: Pyramids of Mars)

From late 2006, UNIT had a base in the Tower of London. (TV: The Christmas Invasion)

From around 2008 on, UNIT possessed at least two flying carrier ships, the Valiant (TV: The Sound of Drums) and the Starling, (COMIC: The Age of Ice) which could be used as bases. The Valiant was destroyed in the 2009 Dalek invasion, (TV: The Stolen Earth) but was rebuilt or replaced by a ship of the same name by the time of the 3W incident. (TV: Death in Heaven)

Branches outside of Great Britain
UNIT Central Control was in Geneva, Switzerland. (TV: Spearhead from Space, et. al.) Martha Jones was briefly attached to Geneva when UNIT was tasked with handling security for the CERN project (AUDIO: Lost Souls)

The French division of UNIT was known as NUIT (or Nations Unies Intelligence Taskforce). (PROSE: The Dying Days)

The Russian division was named ОГРОН or OGRON. This stood for Operativnaya Gruppa Rasvedkoy Obyedinyonnih Natsiy, which roughly translated as United Nations Reconnaissance Operations Group. (PROSE: Emotional Chemistry)

South-East Asia possessed a multi-national UNIT contingent, UNIT-SEA, headquartered in Singapore. (PROSE: Bullet Time)

UNIT had a Japanese division by 2010. (COMIC: The Golden Ones)

Kriegeskind Castle in West Germany was converted into a UNIT base when the organisation was formed, serving as both a research centre and military outpost. It was destroyed following a paranormal outbreak. (AUDIO: Old Soldiers)

UNIT had Osterhagen Stations in Germany, Argentina, Liberia and China. (TV: Journey's End)

UNIT had a branch in North America. (AUDIO: The Dalek Transaction) By 2009, New York City had a UNIT base, carrying out projects like Project Indigo. The base was later heavily damaged, if not destroyed, by the Daleks. (TV: The Stolen Earth)

Australia's UNIT base was underwater, in the Sydney harbour; it contained a museum of alien relics. In 2010 it came under attack by the Skith. (COMIC: The Age of Ice)

Rivals
One division within the Central Intelligence Agency headed by a man known only as Control was a rival of sorts to UNIT. (PROSE: The Devil Goblins from Neptune) A few years later, another American, Bill Filer, worked on friendly terms with UNIT. (TV: The Claws of Axos)

In Britain, UNIT would come into conflict with a domestic anti-alien agency named ICIS (Internal Counter-Intelligence Service), who had a nationalist agenda. (AUDIO: The Wasting) While not running into conflict with them, they were viewed with contempt by both the Forge, (AUDIO: Project: Twilight) and MI6. Under Director Woodrow, MI6 became aware of an alien incursion in London, but deliberately did not mention it to UNIT and tried to handle the situation themselves; this led to the agency being massacred by Cybermen and an unprepared Earth being assaulted. (COMIC: The Flood)

An internal conspiracy within UNIT, the Cortez Project, attempted to massacre any alien, hostile or not, that arrived on Earth. Its existence was exposed in 1997, and UNIT began hunting down its cells. (PROSE: Bullet Time)

Organisation
UNIT's status was supported by enabling legislation that allowed it to assume emergency powers when necessary. Although it operated under the authority of the United Nations, its members were seconded from the host country's military and were still bound to obey that chain of command. Lethbridge-Stewart, for example, reported to the Ministry of Defence and the Prime Minister. (TV: Terror of the Zygons) However, when such orders conflicted, appeals could be made to Geneva. The Enabling Acts helped establishing jurisdictional guidelines: article 17 of the Third Enabling Act set up Geneva's role, while article 18 was "Matters of Domestic Concern" and stated in such cases, UNIT "will place itself at the disposal of the host nation in all respects". (TV: The Time Monster, The Green Death)

Due to the international nature of the organisation, it was viewed with suspicion by local military and national security agencies, who felt that it might impinge on their sovereignty. UNIT's existence was known to the public, but mainly as a security organisation; its actual agenda was classified. In the United Kingdom, its secrecy was guaranteed by the Official Secrets Act. (TV: The Time Monster onwards) Some believed it to be a kind of covert counter-terrorist unit.

Despite the change of name to the Unified Intelligence Taskforce, the United Nations commanded and funded UNIT. (TV: The Sontaran Stratagem/The Poison Sky, Children of Earth: Day One)

Equipment
Its personnel had a wide range of weaponry to call on, some custom-made to combat specific threats. Standard weaponry of UNIT in the early 21st century consisted of G36 and G36C assault rifles, M4A1 assault rifles, limited numbers of K23B-styled M4s seen in the episode, The Poison Sky. SIG-Sauer P226 pistols are seen as their main sidearm, as well as heavy weapons such as the FIM-92A Stinger and the AT4 rocket launcher. The standard issue firearm in the 1970s was the L1A1 SLR, a British version of the FN FAL, which was the current rifle used by the British Army. In the late 1990s, UNIT troops were armed with the Steyr AUG assault rifles. (TV: Battlefield) As the Brigadier explained to the Doctor, these were armour-piercing munitions for use against robots, explosive rounds for Yetis, silver-tipped rounds and gold-tipped rounds for use against Cybermen. (TV: Battlefield) UNIT had a laser rifle at its disposal to deal with a Krynoid, though the weapon did not manage to kill it. (TV: The Seeds of Doom)

UNIT had access to the USS Calvin (a ship) and Octopus Rock (an advanced deep-sea submarine). They also had experimental diving suits made of dwarf star alloy capable of surviving miles below the surface. (AUDIO: Submission)

20th century
Early in its history, UNIT troops and officers wore one-piece beige coveralls with a green/grey shirt and silver/green tie with sand-coloured berets not unlike the British Special Air Service. (TV: The Invasion through TV: Doctor Who and the Silurians) Apart from Brigadier Lethbridge-Stewart, who retained his regular uniform, the exceptions to this were new futuristic-looking uniforms, which consisted of a zip-up jacket without lapels worn over a rolled-neck sweater, (TV: The Ambassadors of Death) and combat gear, as worn by the troops stationed at the Inferno Project in Eastchester. (TV: Inferno)

They reverted to uniforms not unlike that worn by the British Army, but with the addition of UNIT badges. (TV: Terror of the Autons through The Seeds of Doom)

In the 1990s they retained the standard military look, with the addition of a blue cap (with blue representing the United Nations). (TV: Battlefield)

21st century
By 2006, UNIT troops had adopted a paramilitary all-black look, with scarlet berets. (TV: The Christmas Invasion) Officers wore service dress (such as British Army No. 2 Dress or US Army Class A). (TV: Fragments, The Sontaran Stratagem, The Stolen Earth) As an alternative, officers could wear a black version of service dress with the UNIT beret. (TV: Turn Left)

By the time of Kate Stewart's leadership, troops wore black body armour with black helmets and tinted goggles. (TV: The Power of Three) Officers such as Colonel Ahmed wore a navy blue jacket with a white shirt and tie. (TV: Death in Heaven)

Divisions
UNIT maintained a number of specialised departments. One, the Paranormal Division, in which Lieutenant Hamlet Macbeth investigated psychic powers and phenomena. (PROSE: The Left-Handed Hummingbird) UNIT Broadsword was UNIT's intelligence wing and Special Ops division. (PROSE: No Future) It also maintained the Warehouse, a place to store alien artefacts; security breaches at this and similar facilities were handled by the Containment Team. (HOMEVID: Auton) Internal affairs were handled by the Internal Security Division. (HOMEVID: Auton 2: Sentinel) UNIT also maintained a warehouse known as the Black Archive. (TV: Enemy of the Bane)

Call signs
UNIT used a variety of call signs and code words for their agents. The most common call sign was Greyhound. By convention the senior officer (usually Brigadier Lethbridge-Stewart) was Greyhound One (TV: Invasion of the Dinosaurs) or Greyhound Leader. Other Greyhounds included Mike Yates as Greyhound Two, (TV: The Dæmons) Martha Jones as Greyhound Six, and Ross Jenkins as Greyhound Forty. (TV: The Sontaran Stratagem) The commander of operations was often called Trap One, with both Lethbridge-Stewart (TV: Invasion of the Dinosaurs) and Colonel Mace (TV: The Sontaran Stratagem) using the call sign at times. An alternative term was Watchtower. (TV: Doctor Who and the Silurians)

More unusual were the call signs used during the first World Peace Conference, which were based on planets of the Sol system, with the Brigadier as Jupiter and Mike Yates as Venus. (TV: The Mind of Evil) Lieutenant Richards, commanding a missile convoy, was designated Salamander Six-Zero. Brigadier Bambera, in the same operation, was Seabird. (TV: Battlefield)

Helicopter call signs included Windmill 347, (TV: The Mind of Evil) Eagle (TV: The Green Death) and "Uniform November Nine-Zero", (TV: Battlefield) whilst the Valiant was Hawk Major. (TV: The Poison Sky). UNIT's call sign for the TARDIS was Blue Eagle. (TV: The Day of the Doctor)

Alternate timeline versions
The Seventh Doctor visited one timeline in which humans had made peace with the Silurians after the Wenley Moor affair. In this universe, United Races Intelligence Command or URIC had replaced UNIT. An alternative version of Muriel Frost headed the organisation, following the death of the Brigadier in a bomb attack; this world's Doctor was killed in the same attack. (COMIC: Final Genesis)

Another alternate outcome of the Wenley Moor incident saw the Silurians conquer Earth, with the remnants of UNIT fighting a vicious insurgency against them. (PROSE: Blood Heat)

A deliberately altered timeline saw UNIT fighting a counter-insurgency against a British anarchist terrorist group named Black Star. A plain-clothes division named Broadsword had been created. (PROSE: No Future)

In several possible timelines, UNIT was replaced further into the 21st century. In one, it was replaced by the more militant UNISYC (United Nations Intelligence Security Yard Corps). (PROSE: Alien Bodies) In another, it was superseded by the global military PRISM. (PROSE: The Indestructible Man)

UNIT in parallel worlds
The fascist Britain in a parallel universe the Third Doctor visited had its own version of UNIT: the Republican Security Forces. (TV: Inferno) In Donna's World, UNIT soldiers retrieved the dead body of the Tenth Doctor following the Christmas Star incident, and later a division of UNIT worked with Rose Tyler to reverse-engineer the TARDIS and allow Donna Noble to go back in time and make her younger self turn left instead of right at a junction. (TV: Turn Left)

Name

 * Following the broadcast of the 2005 series, in his regular column in Doctor Who Magazine #360 (August 2005), executive producer Russell T Davies explained that the United Nations were no longer happy to be associated with the organisation, and its full name could not now be used. However, the "UNIT" and "UN" abbreviations could still be used, as long as it was not explained what the letters stood for. The modified "Unified Intelligence Taskforce" name was first uttered on-screen in The Sontaran Stratagem, although the same episode includes a line of dialogue indicating the United Nations still supports UNIT with funding; in addition, the acronym as shown on the organisation's insignia still nearly defines U.N.I.T. as separate words.

The Making of Doctor Who

 * According to the non-narrative source The Making of Doctor Who, UNIT was overseen by a Commander-in-Chief in Geneva in the early 1970s.

UNIT website
According to the tie-in website for UNIT, UNIT was formed "in response" to a series of London Underground incidents in 1968, referring to the 1968 story TV: The Web of Fear.

A press statement on the UNIT website that was embargoed until 31 January 2005 states their official position on 13 soldiers that died during manoeuvres investigating reports of "an extreme chemical pollution" in the area.

A press statement embargoed until 31 March 2005, predating UNIT New York City Base's appearance in The Stolen Earth, mentions UNIT having its New York City presence expanded by Major A Highway's "lead up" of UNIT's New York Liaison Office. Major A Highway also pays tribute to his predessor and "old friend", Major C Jones, when she and her colleagues were lost during the Jersey Tollgate Situation.

The UNIT website also showed that UNIT held at least four annual conferences, at least one of which was based in Maidstone Barracks in Kent. The 4th Annual conference on Threat Containment and Response had confirmed seminars such as "Looking upwards rather than outwards", "Civillians [sic] and confusion", "Extreme press relations" and "Alone in a crowd".

Other matters

 * In 1984, a comedic stage play titled Recall UNIT: The Great Tea-Bag Mystery was produced, written by Richard Franklin (Captain Mike Yates) who also reprised his character in the play. The cast included Nicholas Courtney as the Brigadier and John Levene as Sergeant Benton and was performed between 20 August and 24 August as part of the.
 * The UNIT vehicles and the mobile headquarters used in many of the adventures from 1969-1975 were BBC Outside Broadcast vans used by the BBC production unit, with the BBC logos on the vehicles covered up.
 * Several non-individualised UNIT ranks, such as commander, medic and soldier, are used in the Doctor Who: Legacy mobile game both as allies and as enemies