Lieutenant Reginald Endicott "Reg" Barclay III was a highly talented Starfleet systems diagnostic engineer. He always appeared to be nervous and lacking in confidence, stammering profusely, and was known to be reclusive and extremely introverted. As a result of these traits, some crewmembers began to refer to him as "Broccoli."

For the full biography for Lieutenant Barclay prior to his interaction with Voyager please click here

In 2371, Barclay transferred to Jupiter Station and worked as part of the original holo-engineering team in Dr. Lewis Zimmerman's holographic laboratory to test the Emergency Medical Hologram's interpersonal skills.

(VOY: "Projections")

By 2376, after working with Dr. Lewis Zimmerman on the EMH mark I at Jupiter Station, he became obsessed with the return of the starship USS Voyager from the Delta Quadrant, and petitioned to be assigned to the Pathfinder Project at the Communications Research Center. Barclay's holo-addiction returned after he created a semi-accurate recreation of the starship and its crew, who all really liked and heavily relied upon him because of his programming. He even kept a pet cat, which he named "Neelix".

It was Barclay's efforts that led to two-way communication being made with Voyager, when he came up with the idea of directing a tachyon beam towards an approaching Class B itinerant pulsar to send a signal through an artificial micro-wormhole to be generated from the resulting gravimetric surge. Unfortunately, Barclay chose to suggest his idea in the middle of an official briefing with Admiral Owen Paris, against Commander Harkins' orders. Barclay was dismissed from the project by Harkins on temporary leave, after he discovered the engineer's obsession with Voyager, despite Barclay's protests.

Barclay returned to the CRC, and again activated the Voyager holoprogram. He attempted to use the program to activate his plan to use the MIDAS array to communicate with the real ship, using the holographic characters 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, having received Barclay's message - finally, two way communication had been established with the ship. Tom Paris toasted with Voyager's crew christening Barclay an honorary member. Following Barclay's success in communicating with Voyager he was rewarded with a promotion to full Lieutenant.

(VOY: "Pathfinder")

Barclay had developed a hologram based on his image to help Voyager. However, he sent it to the Delta Quadrant twice but had no success. Yet his superiors insisted that a spatial phenomenon may have been responsible. His suspicions grew so crazy that he interrupted a children's tour saying that the Borg or Romulans were involved but he was sent off on vacation to relax. By his design, he met Deanna Troi again. Based on his own accord, his luck had improved, at least for a while, including the time around Commander Geordi La Forge's birthday party, but then things went sour. He told her his troubles, and even mentioned that his girlfriend, Leosa, had left him after he told her everything about the Pathfinder and his hologram. Starfleet had her detained, where it was revealed to Barclay that Leosa was a dabo girl, rather than a teacher as she lead him to believe. With Troi's help, they discovered that a trio of Ferengi had intercepted his hologram and reprogrammed it to deceive Voyager, with a few hints from Leosa that Borg nanoprobes were worth a lot of latinum. It was apparent that the Ferengi planned to use a geodesic fold between the Alpha and Delta Quadrants with the hologram tricking Voyager into it with false inoculations and shielding, which would kill everyone aboard. Barclay posed as his hologram, bluffing to the Ferengi that Voyager was bound to survive and was going to blast them on the other side of the fold. Due to luck, Voyager was saved. Barclay made another hologram, this time with more security features to demand to others to "Identify yourself!"

(VOY: "Inside Man")

In 2378, Barclay was on duty at the Communications Center while Admiral Paris was visiting. During his visit, long range sensors detected a Borg transwarp conduit opening just outside the Sol system. Barclay reported the information to the several visiting Admirals, as another Borg attack was feared. When a Borg sphere emerged, and then quickly exploded to reveal Voyager, Reg was one of the first to welcome them home.