Lieutenant Reginald "Reg" Endicott Barclay III was a highly-talented Human Starfleet systems diagnostic engineer who lived in the 24th century. He frequently displayed nervous behavior, demonstrated a noticeable lack in confidence, stammered profusely, was extremely introverted, and occasionally bumbled. These traits engendered the derision of some of his shipmates on the USS Enterprise-D – with some even going as far as calling him "Lieutenant Broccoli" behind his back or, on unfortunate occasions, to his face.
During Barclay's attendance at Starfleet Academy, his reclusive tendencies escaped the attentions of neither his classmates nor his service record. Despite this, Barclay graduated and received a commendation by serving competently in Starfleet for many years. During his service aboard the USS Zhukov, he earned satisfactory ratings and – when he then transferred to the Enterprise-D – the Zhukov's commanding officer, Captain Gleason, spoke highly of Barclay to his new ship's crew. (TNG: "Hollow Pursuits")
Due to his nervousness and lack of confidence, many members of the Enterprise crew initially referred to him as "Lieutenant Broccoli", a play on the name Barclay, coined by Wesley Crusher. He was initially disliked by members of the crew, not only due to the fact he seemed constantly nervous and on edge, but also because he was routinely late for duty and often wound up on report for seemingly not performing to the best of his ability. As a result, he was the first member of the Enterprise crew to be given an 'unsatisfactory' rating in his evaluation. Riker and La Forge attempted to get him transferred off the ship, not believing he was competent enough to serve on the Federation flagship (with Riker even suggesting that Captain Gleason had intentionally been high in his praise of Barclay in order to get rid of a troublesome officer). Captain Picard however refused to simply transfer him off the ship and it was because of him and Geordi La Forge's encouragement that Barclay's confidence began to increase. (TNG: "Hollow Pursuits")
During the first major Borg incursion of the Federation in late 2366, Barclay worked on repairs with Sherman after the Enterprise-D crew – in an unsuccessful attempt to destroy the Borg cube – emitted a burst of energy from their ship's deflector dish. (TNG: "The Best of Both Worlds, Part II")
Following an encounter with an alien probe in 2367, Barclay's IQ rose to somewhere between 1200 and 1450. During the time he possessed this enhanced intellect, Barclay was more confident, outgoing, and sure of himself – even correcting the math and physics theories of a holographic representation of Albert Einstein on the holodeck. Barclay was able to use the holodeck to integrate his mind into the ship's computer, effectively taking complete control. Unknown to Barclay, the Cytherians (the creators of the probe) set this in motion so that he would bring the Enterprise-D to them, as this was their species' preferred method of investigating new races. All attempts to disconnect or dissuade him were unsuccessful, and he created a subspace distortion that brought the Enterprise-D to Cytherian. After this encounter, Barclay was returned to his previous self, but he did retain a bit of the confidence and intelligence that the experience gave him. (TNG: "The Nth Degree")
In 2369, Barclay assisted Alexander Rozhenko with writing a holodeck program of Deadwood, South Dakota in the Ancient West. Barclay included a prostitute and brothel in the simulation (likely unthinkingly going a bit too far for historical accuracy in a child's program), which Lieutenant Worf did not appreciate for his son's sake. (TNG: "A Fistful of Datas")
Later that year, Barclay inadvertently released the holographic representation of Professor James Moriarty from his confines in the computer memory core of the Enterprise-D, while conducting a diagnostic into a failure of the holodeck matrix diodes, which turned out to have been caused by Moriarty himself. Upon activation, Moriarty briefly explained his history to Barclay and, realizing that over four years had passed, Moriarty deduced that Captain Picard had merely promised to research a way for him to live in the real world in order to get him to release a hostage he had taken at the time. Barclay defended Picard, saying the captain would never go back on his word and promised to report the incident to his superiors, which he did.
Barclay, Picard, and Data then reactivated the program to speak to Moriarty, who expressed his desire to leave the holodeck. Barclay then proposed an idea to use transporter pattern enhancers to beam Moriarty off the hologrid and thus into the "real world." This idea ultimately failed, since it was nothing more than a ruse to trick the three officers into giving him control of the ship by use of a holographic simulation of the Enterprise-D within the Sherlock Holmes program. However, the failure of the experiment led Data to discover the trickery and, on Captain Picard's suggestion, he and Barclay managed to create a separate simulation within both programs, thereby fooling Moriarty with his own plan. Thinking he was free, Moriarty relinquished control of the Enterprise, allowing Barclay to store his program in an enhancement module, where he could safely explore the galaxy without causing any further trouble.
Barclay, along with the senior staff, later convened in the observation lounge to discuss recent events, where Captain Picard instructed him to keep the module safe. Picard also jokingly wondered if their reality "might be nothing more than an elaborate simulation being run inside a little device... sitting on someone else's table," which prompted Barclay, after the meeting had concluded, to test the idea by ordering the computer to "end program." Satisfied his life wasn't a simulation when nothing happened, he picked up the module and left as well. (TNG: "Ship in a Bottle")
The following year, Barclay had the rather dubious honor of becoming the eponymous person for a newly-created illness, "Barclay's Protomorphosis Syndrome". He, in common with the rest of the crew, became affected when a treatment for the mild Urodelan flu – provided by Doctor Beverly Crusher – activated a recessive gene, causing him to mutate into a spider-like creature. It was only down to the efforts of Captain Picard and Lieutenant Commander Data that Barclay and the rest of the crew were saved; as they were off the ship when the incident occured, they were able to successfully develop a retrovirus and release it using the ventilation systems. As he was the first known patient of the disorder, Dr. Crusher decided to name the newly discovered illness in Barclay's honor. (TNG: "Genesis")
In 2375, Lieutenant Commander Worf and Chief O'Brien specifically mentioned that nobody could forget Barclay when remembering old friends on the Enterprise. O'Brien and Worf remembered him most for his extravagant "Three Musketeers" program that he often invited the crew to join him in. (DS9: "Image in the Sand")
At sometime prior to 2371, Barclay transferred to Jupiter Station and worked as part of the original holo-engineering team in Dr. Lewis Zimmerman's holographic laboratory, assigned to test the Emergency Medical Hologram's interpersonal skills. (VOY: "Projections")
Barclay was assigned to the new USS Enterprise-E before the Battle of Sector 001 in 2373. He traveled into the past with the rest of the ship's crew to the day before Earth's First Contact with the Vulcans, where he met the noted inventor Dr. Zefram Cochrane. As one of his fans, Barclay was thrilled at the opportunity to shake Cochrane's hand, so much so (in fact) that Lieutenant Commander Geordi La Forge found himself having to remind Barclay to calm down and continue his work, helping Cochrane repair the Phoenix. Barclay also obtained Geordi's approval and input on a makeshift component that Barclay and other engineers from the Enterprise-E intended to use to replace the Phoenix's warp plasma conduit. (Star Trek: First Contact)
The Pathfinder Project
In 2374, Barclay moved into an apartment in San Francisco. In 2376, Barclay transferred to the Pathfinder Project at Starfleet's Communications Research Center, endeavoring to return the starship USS Voyager to the Alpha Quadrant from the distant Delta Quadrant. To assist in this goal, Barclay created a holographic recreation of the vessel and its crew, a program that enabled him to experiment with different solutions.
Later that year, Barclay – with the assistance of the USS Voyager simulation – devised the idea of using the MIDAS array to direct a tachyon beam towards an approaching Class B itinerant pulsar, thus generating an artificial micro-wormhole. This wormhole could then be directed towards Voyager's likely locations and used to communicate with the ship. Unfortunately, Commander Peter Harkins turned down his idea as impractical.
However, Barclay was unable to contain his enthusiasm during an inspection of the research facility by Admiral Paris. This prompted Harkins to send Barclay home for the rest of the day. Barclay disobeyed, and instead returned to his simulation to refine his ideas. When Harkins later discovered Barclay in the simulation, he was suspended by Harkins, pending a psychological evaluation.
Barclay was unable to accept this and first appealed to Admiral Paris, then broke into the Communications Center. He attempted to go forward with his plan, but was discovered. To prevent himself from being interrupted, Barclay activated the holographic recreation of Voyager, using the holographic crew to protect and assist him. Just as Harkins used a simulated warp core breach to end the program, Captain Kathryn Janeway hailed the Communications Center from the Delta Quadrant, having received Barclay's message. With this (albeit brief) two-way communication with the ship, ship's logs, research data and a personal message for Tom Paris from his father was able to be transmitted, and Barclay's ideas were vindicated. The crew of Voyager later toasted their unmet hero who had established the link, christening Barclay as an honorary member of the crew. (VOY: "Pathfinder")
In 2377, Barclay returned to Jupiter Station with Voyager's EMH, who had been transmitted to the Alpha Quadrant using the MIDAS Array connection. Barclay had informed The Doctor that his creator, Doctor Zimmerman, had been diagnosed with acute sub-cellular degradation and was dying. Although Zimmerman initially refused The Doctor's assistance, Barclay – who had also enlisted the aid of Counselor Deanna Troi – helped The Doctor persuade Zimmerman to realize that The Doctor's assistance was the best course of action in order to save his life. (VOY: "Life Line")
Later that year, Barclay discovered that a romantic acquaintance of his, Leosa, had been using him to gain information on Voyager and the Pathfinder project. It turned out the information she had obtained was sold to a group of Ferengi who had used it to alter a holographic program Barclay sent to Voyager, with instructions to kill the crew and reprogram the shields to withstand a geodesic fold they had created between the Alpha and Delta Quadrants. Even though their plan was to steal the Borg technology in Seven of Nine's body (which was worth a fortune in latinum), Barclay – with the help of Counselor Troi – was able to fool the Ferengi into abandoning their own plan, thereby saving Voyager. (VOY: "Inside Man")
In 2378, Barclay informed Admiral Paris that a draft version of the holonovel Photons Be Free, written by The Doctor, had been released early, becoming popular in thousands of holosuites across the Federation. Barclay was present during a hearing to decide The Doctor's rights as the creator of the work. (VOY: "Author, Author")
Later that year, Barclay was on duty at the Communications Center when long-range sensors detected a Borg transwarp conduit opening just outside the Sol system. He quickly reported this information to several visiting Admirals. When a Borg sphere then emerged from the transwarp conduit and exploded to reveal Voyager, Barclay was one of the first to welcome the starship's crew home. (VOY: "Endgame")
Medical and psychological record
Barclay suffered from severe transporter phobia, although he later overcame this psychological barrier. (TNG: "Realm of Fear") He was additionally a hypochondriac and was prone to self-diagnosis; he once thought himself to have transporter psychosis and, on another occasion, he believed himself to have Terellian Death Syndrome. (TNG: "Genesis")
Struggle with holo-addiction
Sometime prior to 2366, Barclay began to suffer from holo-addiction, becoming addicted to the fantasy worlds and stories the holodeck could create. This addiction continued after he transferred to the Enterprise-D, aboard which he had a tendency to spend more time inside the holodeck – where he was more confident and comfortable – than in real social situations. Unlike in normal holoprograms, Barclay used the likenesses of the Enterprise's senior staff to create unusual scenarios wherein he was the hero.
One of his programs was an exact recreation of the Enterprise-D, in which he commonly argued and back-chatted senior officers without fear of any consequences. In one holodeck session, he propelled the holographic representation of Geordi La Forge across Ten Forward and threatened First Officer William Riker, in an attempt to impress the holographic Deanna Troi.
Another recreation of Barclay's was entitled "Barclay Program 15". In this scenario, he engaged in sword fights with "The Three Musketeers", holograms that resembled Jean-Luc Picard, Geordi La Forge and Data, romanced the "Goddess of Empathy", a representation of Deanna Troi, and relaxed with a hologram of Beverly Crusher. Barclay had also created an effigy of William Riker that was an extremely short, bumbling swordsman.
When Barclay's holo-addiction was discovered, Commander Riker was particularly annoyed with him and wanted to delete all programs in which he had used the crew's physical appearances. Counselor Troi objected – as it gave them valuable insight into what was troubling Barclay – but she soon became equally angry, upon seeing the "Goddess of Empathy" recreation of herself (to Riker's amusement, he in turn prevented her from deleting the Goddess for the same reason).
Barclay managed to overcome his addiction with the help of Geordi La Forge. When the Enterprise was in danger of flying herself apart, due to an invidium infection of the computer systems, La Forge encouraged Barclay's imagination and it was he who discovered the infection, which led to the situation being controlled. After a few words from La Forge, Barclay returned to the holodeck and deleted all of his holoprograms but one: Barclay Program 9. The crew soon came to realize he was as important as anyone else on the ship. (TNG: "Hollow Pursuits", "The Nth Degree")
In 2376, Barclay became obsessed with the attempts to return Voyager from the Delta Quadrant. It was due to this obsession that he expressed an interest in becoming involved in the Pathfinder Project. Barclay became dangerously close to suffering a re-lapse of his holo-addiction later that year, when he used the program that recreated the crew of Voyager. His condition returned following his creation of the program; even though it originally began as a tool to test different theories on how to contact the stranded ship, he quickly came to regard the program as another sanctuary, away from the real world.
The program was only semi-accurate; the duplicates of Voyager's crew all really liked and heavily relied upon him because of his programming. They responded to Barclay as though he was their best friend. He joked with Harry Kim, played poker with the senior staff, enjoyed hoverball with Tom Paris, and assisted B'Elanna Torres with warp core calibrations. He even got a massage from The Doctor, on one occasion. Barclay once told Deanna Troi that he slept better in his holographic quarters than he ever did in his apartment.
The fascination with Voyager that Barclay had developed, as well as his unauthorized interactions with the holographic crew, expedited his dismissal from the Pathfinder Project. However, once Barclay used the program to prove his theory correct, the time he spent in the Voyager simulation dwindled, along with his need for the holodeck. (VOY: "Pathfinder", "Life Line", "Inside Man", "Author, Author")
Geordi La Forge
Geordi La Forge was intially Barclay's superior officer on the Enterprise-D. When he first came aboard, La Forge remarked that Barclay was "always late, never gives his best effort, just slides by", though after being instructed by Captain Picard to find a way to integrate him into the crew, La Forge began to encourage Barclay and praise him on his efforts.
On the subject of his holo-addiction, La Forge tried to make Barclay feel as though he could interact with the crew and didn't have to confine himself to the holodeck. Barclay once said that he thought La Forge was the most real to him of any of the crew.
This cooperation carried over to the Enterprise-E, where Barclay continued to serve under La Forge. When the ship traveled back in time to 2063, Barclay's meeting with Zefram Cochrane was supervised by La Forge. (Star Trek: First Contact)
In February 2377, Barclay attended La Forge's birthday party and showed him the specifications for a hologram he planned to send to the USS Voyager in the Delta Quadrant. La Forge told Barclay he was proud of him. (VOY: "Inside Man")
Barclay first met Lewis Zimmerman while working on development of the EMH Mark I in 2371. The two of them later developed a mutual respect for one another, Barclay being instrumental in the forging of Zimmerman's friendship with The Doctor.
When Zimmerman believed he was reaching the end stage of his terminal illness, he included Barclay in his own last will and testament, giving him his collection of holographic art which included the "Woman in Four Dimensions" piece. In addition, Zimmerman requested that Starfleet allow Barclay to complete his Trojan Horse Project as he trusted Barclay to be the only engineer that would get it done. (VOY: "Projections", "Life Line")
Barclay met Counselor Troi during his time on the Enterprise-D and quickly developed an attraction to her, even going as far as to use her image in one of his holoprograms featuring her as his lover. (TNG: "Hollow Pursuits")
In 2376, at Barclay's request, she visited him to discuss his feelings toward his new assignment at Starfleet's Communications Research Center. He opened up to her, noting that work at the CRC was nothing like on the Enterprise, where there was a feeling of family. (VOY: "Pathfinder")
As a favor for Barclay, she even asked Captain Jean-Luc Picard for leave from the Enterprise to convince Lewis Zimmerman to accept treatment from Voyager's EMH and assisted Barclay with a ruse to disrupt The Doctor's programming, saying, "Traditional therapy wasn't getting [them] anywhere." (VOY: "Life Line")
In 2377, she again helped Barclay by influencing him to realize that Leosa was using him to gain information on Voyager, encouraging him to report it to his superiors. Troi later invited him on a double date with her and Commander Riker, and a real teacher friend of his called Maril, as a way for him to get out and meet people. (VOY: "Inside Man")
During a severe malfunction, one of The Doctor's recurring delusions was Barclay who tried to convince him that he was in fact Lewis Zimmerman and that he was trapped in a holographic Voyager. In order to end the simulation, "Lewis" had to destroy the warp core. Fortunately, a delusion of Chakotay convinced him otherwise. The Chakotay hallucination claimed that Barclay was part of the team that created him. (VOY: "Projections")
Barclay first met the The Doctor when he took him to Jupiter Station to help Dr. Zimmerman, though the two had previously corresponded thanks to the communication system he developed using the MIDAS Array. It was Barclay who had informed The Doctor of Zimmerman's illness, and it was he who initially convinced him to stay and treat Zimmerman, even when he refused all help. (VOY: "Life Line")
When Voyager received the altered Barclay hologram, it was indeed The Doctor who first realized something was wrong with the program, stating the real Barclay never exhibited rude and careless traits as he had observed in the hologram. (VOY: "Inside Man")
During The Doctor's hearing to decide his rights as a hologram, Barclay defended him, recounting how he had "travelled half-way across the galaxy" to care for Dr. Zimmerman. He compared it to a son showing his "old man" what he had become so he could be proud of him. When it was ruled that The Doctor had the right to control his own work, Barclay congratulated him. (VOY: "Author, Author")
Commander Peter Harkins was Barclay's superior officer on the Pathfinder Project. He once invited Barclay to dinner with his wife, Angie, and her sister, with the aim of setting the two up on a date though Barclay refused, preferring to concentrate on his work.
Although he believed Barclay to be a competent engineer, he was skeptical of some of his theories, in part due to Barclay's history. When Barclay developed the idea to use the MIDAS Array to create an artificial singularity to Voyager, Harkins dismissed it as a "cock-eyed theory" that only existed in his head and ordered him to abandon the idea. However, determined to prove his theory right, Barclay bypassed Harkins, going straight to Admiral Paris. This caused whatever personal relationship they had to deteriorate.
Harkins was the one who later discovered Barclay had recreated the Voyager crew on the holodeck. He believed he had been a friend to Barclay by allowing him some leeway but, upon finding him there and realizing his past history with holo-addiction, he pulled him off the project and told him to get counseling.
Barclay initially followed Harkins' instructions and went home, where he talked about the situation with Deanna Troi. Later the same night, he decided to disobey Harkins' orders by breaking into the Pathfinder lab and accessing the MIDAS Array in an attempt to prove this theory correct. When Harkins discovered Barclay in the lab, he ordered security to apprehend him, but Barclay activated the Voyager scenario and locked out all holodeck controls. He continued with this plan to send a message to Voyager from within the simulation and used the holographic characters to stop the security officers. Harkins eventually managed to corner him by initiating a warp core breach in the simulation, forcing Barclay to close it down.
Harkins then arrested Barclay for breaking into the lab and using equipment without authorization. But before the security officers could take him away, a message came through from Voyager. Barclay's plan had worked. Harkins subsequently apologized for doubting him. (VOY: "Pathfinder")
After Barclay tried to send his hologram to Voyager, he became obsessed with finding the reason why it had failed to reach them, even blaming the Borg and the Romulans of intercepting the message. It was Harkins who ordered him to take a week's leave and to return when he was more focused and relaxed. Barclay initially objected to the idea but Harkins forced the issue, reminding him that he was his superior. He did, however, offer to ask his cousin to allow Barclay to stay in a Malaysian beach house she owned, though Barclay refused, preferring to seek out Deanna Troi's help instead. (VOY: "Inside Man")
Barclay had a deep affection for cats and, for some reason, the cats returned this affection. Spot, Data's pet cat, found only her owner and the lieutenant to be suitable for her mercurial tastes. (TNG: "Genesis")
Though Barclay had never physically met Neelix, he did name his cat for him, suggesting at least some level of respect or admiration. He even programmed his Voyager simulation to have the Talaxian purr. (VOY: "Pathfinder", "Life Line")
Barclay had a series of unsuccessful romantic affiliations, primarily due to his nervous nature – something which caused him to focus more on his work than anything else.
Despite this, Barclay did begin to pursue a relationship with Hope, the sister-in-law of his superior officer Peter Harkins, in mid-2376. Their romance did not last very long, however.
Barclay began to see Leosa by early 2377. When this relationship turned out to be a ruse, Barclay decided not to pursue another relationship. When he was then introduced to Maril, a teacher and friend of William Riker by Deanna Troi, in an attempt to help Barclay. (VOY: "Pathfinder", "Inside Man")
Alternate realities and timelines
In 2404 of an alternate timeline, Barclay managed to stop stuttering (although his stammering resurfaced when he was caught in a lie). He held the rank of commander and became a teacher at Starfleet Academy, teaching a class about the Borg. Barclay later helped Admiral Janeway in an attempt to travel back in time and return Voyager to Earth sooner than had been done by the vessel's crew. The Doctor learned the truth from him after the addled Tuvok managed to warn him that Janeway was leaving forever. (VOY: "Endgame")
Barclay has been holographically duplicated on at least two occasions:
- In 2371, the USS Voyager encountered a subspace anomaly which caused a feedback surge through The Doctor's holographic matrix, generating a holographic hallucination. Among the projections created was one of Lieutenant Barclay, who insisted the EMH was Doctor Lewis Zimmerman and that Voyager was merely a simulation he had been running at Jupiter Station. Eventually, the crew of Voyager successfully managed to extract The Doctor's program and deactivate the hallucination. (VOY: "Projections")
- Barclay created a holographic duplicate of himself designed to be transmitted to Voyager where it could aid them in their trip home to Earth. In its first transmission, it was intercepted and reprogrammed as part of a profit scheme devised by three Ferengi, but their plan was ultimately discovered by Barclay himself and the hologram was deactivated. (VOY: "Inside Man")
"You know, the people that I create in there are m... more real to me than anyone I meet out here. Except... maybe you, Commander."
"I need you out here, Reg – now more than ever."
"Mr. Barclay! Everyone's still trying to figure out exactly how you did it."
"Well, it... it just occurred to me that I could set up a frequency harmonic between the deflector and the shield grid, using the warp field generator as a power flow anti-attenuator, and that, of course, naturally created an amplification of the inherent energy output. "
"Uh-huh, I see that...."
- - William Riker and Barclay, after the latter officer increased the Enterprise's shield strength to three hundred percent. (TNG: "The Nth Degree")
"I've lost myself, Deanna."
"In Voyager. I've become obsessed... with Voyager."
"Dr. Cochrane, I know this sounds silly, but could I shake your hand? [Cochrane reluctantly shakes it] Oh! Thank you, Doctor! You have no idea what an honor it is to work with you on this project!"
"I never thought I would ever meet the man who invented warp drive! I..."
"Hmm...? Oh! Yes, of course. I'm sorry...."
- - Barclay and Geordi La Forge, after meeting Zefram Cochrane. (Star Trek: First Contact)
"He traveled half-way across the galaxy to care for Lewis Zimmerman, the man who created his program. It was like a son who wanted to show his father what he'd become, so the old man would be proud of him. And if you ask me, he was."
Barclay is additionally referenced in the following episodes:
- TNG: "The Best of Both Worlds, Part II", "A Fistful of Datas"
- DS9: "Image in the Sand"
- ENT: "These Are the Voyages...".
The character of Barclay was conceived by Gene Roddenberry. "He realized that that type of character was missing from the programme," stated Dwight Schultz, "and eventually said, 'Lets fill that spot.'" (TV Zone, issue 139) Schultz believed that, upon inventing the persona, the writing staff was attempting to create a ground-breakingly relatable character. "I think they thought, 'Hey, why don't we write a character who is just like the rest of the Human race and put him on the Bridge. I bet our fandom will identify with him.'" (Star Trek Monthly issue 30, p. 32)
When the role of Barclay began to be written, he was described as a contradiction in terms. "But you see, it really has to do with how brilliant he is," noted Dwight Schultz. "Can you overlook his social skills problem to get to his intelligence, his capability?" (Starlog #222)
According to an early script for "Hollow Pursuits", the character was originally named Endicott Reginald Barclay III, but the first and middle names were later switched. In the same script's teaser description, Barclay was referred to as "a shy individual with a perpetual frown born of stress and unhappiness between his brows [....] What we notice most about him is that he is uncomfortable around other people to the point of agony... he rarely makes eye contact... when he speaks, he hesitates, desperately afraid of saying the wrong thing... which he occasionally does." 
Barclay was played by actor Dwight Schultz. At the time of his casting, Schultz had been a Star Trek fan for a long time and had asked Rick Berman to consider him if the right part came along. (Captains' Logs: The Unauthorized Complete Trek Voyages, p. 196) Whoopi Goldberg was instrumental in arranging that Schultz play the role of Barclay. "I told her what a big Star Trek fan I was. I asked her what it was like to work with Patrick Stewart [...] and she said, 'You gotta be on that show,'" Schultz related. "She went back and told them. Before I knew it, I got a call from my manager asking me if I would like to do it." (Starlog #222)
As a big fan of science fiction and with an interest in science as well as pseudoscience, Dwight Schultz thought it was "perfect" for him to be involved in Star Trek. "I was the lucky one chosen," he remarked. (TV Zone, issue 139) However, the nature of the part came as something of a surprise to Schultz, who at first thought portraying the character would represent a few days' work involving intensive makeup. "I didn't know Barclay was going to be a recurring character," he explained. "As far as I was concerned, it was a one-time shot. I was a little disappointed, to tell you the truth, when I got the script for 'Hollow Pursuits', that my character wasn't a vein-bulging alien." (Star Trek Monthly issue 30, p. 32) Schultz discovered that Barclay, in fact, was closer to his own offstage personality than the actor's most famous role, Mad Dog Murdoch from The A-Team. He was not afraid that accepting the part of Barclay would lead to type-casting. "When we talked about Barclay, you know, the whole concept of him on the Holodeck, was that he could be four different characters, in one room. He could be something different every time. It doesn't stay that same. It's not a continuation. So, in a sense, you see, there isn't a typing." (Starlog #222)
At the age of forty-three, Dwight Schultz was one of the oldest actors to portray a junior officer, making his first appearance as Barclay holding the rank of lieutenant junior grade. In the actual US Navy, upon which Starfleet ranks are mostly based, lieutenants are normally in their early twenties, having obtained their ranks by virtue of a college degree. For the most part, only officers who entered as enlisted and worked their way up (or "mustang" officers) ever hold this rank beyond the age of thirty.
Partly because he was familiar with not only Whoopi Goldberg but also Brent Spiner and Jonathan Frakes as well as several members of the TNG production crew, Dwight Schultz found that making his first guest-star appearance on the show was not an uncomfortable experience. "This was extraordinarily easy for me," he recalled, "because of all the familiar faces [....] The script was a terrific Walter Mitty type fantasy. I got to kiss Marina Sirtis and work with Gates McFadden as well as do a bit of sword fighting with Patrick Stewart [....] I had a great time." (TV Zone, issue 139)
Finding a way to follow up Barclay's initial appearance was quite challenging and the TNG writing staff struggled with this issue for around a year. They wanted Barclay to reappear in an episode that had a worthwhile story idea, not keen on once again portraying the character as a nervous officer on the holodeck. It was Joe Menosky who eventually devised the means by which they would have Barclay make a second appearance. Recalled Michael Piller, "Joe had this concept of somebody who became super intelligent and said, 'Maybe this could be our Barclay show.'" Brannon Braga commented, "It was a good twist on that particular character which you could only get to with a science-fiction gag." Rick Berman contributed to the depiction of Barclay in "The Nth Degree" by suggesting the idea that he play Cyrano De Bergerac in the outing. (Captains' Logs: The Unauthorized Complete Trek Voyages, pp. 218 & 219)
The makeup department was able to create the spider-like creature seen in "Genesis" by using appliances and latex wrinkles applied to the top of Dwight Schultz's head and upper face, eye appliances, appliances that looked like spider's eyes, and a spider-leg device that protruded from the side of Barclay's head. (Star Trek: Aliens & Artifacts, p. 118)
During early development of Star Trek: Voyager, it was proposed that the holographic main character who ultimately became The Doctor might have the likeness of Barclay and that an episode of Star Trek: The Next Generation's seventh season could feature Barclay working on the hologram. A summary of ongoing development meetings for Voyager, which was written on 6 August 1993, posits, "Barclay would have been working on this program and finally takes a leave to put on the polishing touches (on a TNG episode). He creates the character in his own image." (A Vision of the Future - Star Trek: Voyager, pp. 182 & 183)
Following the appearance of the Barclay hologram in "Projections", the continuation of the real Barclay character was not assured. In a 1996 interview, Dwight Schultz confessed, "I'm almost getting too old to do Barclay, because he's a character who has to change in a different way, or go back, or revert to what he was." (Starlog #222) In an interview from 1997, however, Schultz further contemplated returning as a Star Trek guest star, saying, "Who knows? I could be again someday." (Star Trek Monthly issue 30, p. 37)
Ultimately, Dwight Schultz was very thankful for the opportunities to portray Barclay on TNG. (TV Zone, issue 139) "It was actually quite a brilliant stroke that the writers came up with this completely fallible Human being," he said. "They broke new ground with the character. I didn't do it, the writers did it, and I think they knew it." (Star Trek Monthly issue 30, p. 32) Regarding his TNG appearances, Schultz commented, "I've been blessed with some lovely scripts and a character that people could truly identify with." Indeed, the response from Star Trek fans to Barclay was extreme. "They really do identify with Barclay because he has difficulties," Schultz observed. "He's not the super perfect Starfleet Officer you often see in Star Trek and the audiences love him because of that." (TV Zone, issue 139) Schultz heard many times from Star Trek fans that they very much identified with and related to Barclay. (Star Trek Monthly issue 30, p. 32)
The popularity of the character with Star Trek fans was what lead to Barclay's reappearances following his introduction in "Hollow Pursuits". (Star Trek Monthly issue 30, p. 32) Many fans responded positively to how he is depicted in "The Nth Degree", which Dwight Schultz cited as his favorite episode, partly due to what happens to the character therein (but also because Schultz approved of the possible future for Humanity which that installment suggests). (Starlog #222)
Michael Piller remarked, "[Barclay] is a very interesting character and a great actor." (Captains' Logs: The Unauthorized Complete Trek Voyages, p. 218)
Playmates Toys have released two action figures based on Reginald Barclay; the first, in 1994, was based on his appearances throughout Star Trek: The Next Generation and the second, in 1996, was based on his appearance in the Star Trek: Voyager episode "Projections".
- Barclay appears as a selectable crew member in the non-canon video game Star Trek: Starship Creator, in which his personnel file states he was born in 2340 in Cleveland, Ohio and gained a Masters Degree in Computer Systems from the Daystrom Institute in 2362. It explains he did not attend Starfleet Academy and was instead offered a commission by Starfleet at the rank of Lieutenant Junior Grade, which he accepted. It further states that Barclay's interests are holoprogramming, theater, speculative fiction and self-help books, and that his father is Reginald Barclay II and his mother is Commander Alicia Barclay, both of whom reside in Swansea, Wales.
- In Peter David's novel Imzadi, Barclay is involuntarily cured of his holo-addiction in 2368, when an aged Admiral Riker, having used the Guardian of Forever to travel back in time and prevent the death of Counselor Troi, materializes in the past on the holodeck during one of Barclay's adventures. Disguising his presence by claiming to be an automatic system programmed to activate if Reg used his holoprograms again, Admiral Riker instructs Reg to shut the program down. Reg is so intimidated by the Admiral that he decides never to use the holodeck again. This is inconsistent, however, with the Voyager storyline.
- In Greg Cox's The Q Continuum trilogy, Barclay discovers that the bio-neural gel packs used in the Enterprise-E are capable of absorbing the psionic energy of the galactic barrier, prompting him to suggest that the crew channel the resulting energy into the Enterprise's shields so that they can increase the time that they can remain in the barrier during an attempt to hide from the Calamarain.
- In Diane Duane's novel Dark Mirror, Lieutenant Commander Barclay is Captain Picard's chief bodyguard in the mirror universe. While masquerading as his mirror universe counterpart, Picard notes that Barclay's "slightly crazed creativity" has been redirected, replacing his quirkiness with a more hard-edged sense of danger. Picard promises Mirror Barclay a promotion, but he is killed before this can happen. Upon returning to his own universe, Picard achieves a sort of symmetry by noting a special commendation on the "real" Barclay's record, as a reward for the extra work he has been putting in.
- In the Strange New Worlds short story The Naked Truth, which is set in 2370, Captain Picard orders Barclay to lead his first away mission, installing a new generator core in a space station in the Tarvo system. However, Barclay and his team soon end up fighting for their lives in a Vorel trap.
- Barclay also appears in the John Vornholt novels Gemworld, Book One and Gemworld, Book Two, as a crewmember on the Enterprise-E in 2375.
- In the video game Star Trek: Elite Force II, set in 2380, Barclay serves as temporary chief engineer on the Enterprise-E.
- In the Kirsten Beyer novel Full Circle, Barclay is assigned to the USS Galen, which has been fitted with a quantum slipstream drive and assigned to Project Full Circle, an expeditionary force sent to explore the Delta Quadrant. The novel takes place in the year 2381.