Despite his sense of humor and easygoing conversational manner (especially around other accountants, like Ben Wyatt), his lectures and demonstrations of accounting software (QuickBooks Pro ) are tediously boring; cheerfully delivered in a monotone voice and interspersed with awkward puns related to accounting. Invariably, Andy Dwyer is the only person who finds Barney's wordplay entertaining.
Eager to please, he has offered Ben Wyatt a position at his firm on multiple occasions, being declined each time–though this has not created tension between them. Ben's propensity for reciting his own accounting puns always results in raucous laughter from Barney, who will usually call in Ted (an unseen employee at the firm) to hear Ben's joke. Barney grows more and more enamored with Ben and his puns, and is pitiably disappointed every time Ben rejects a job at the accounting firm.
He first appears in the episode "Leslie's House", when he bursts in, demanding that his class be evaluated. During his presentation, he makes several accounting puns: "The only thing that's taxing is deciding what software to buy", "When it comes to accounting software, there's no accounting for taste" as well as "...and that concludes a quick look at QuickBooks Pro". Everyone at the dinner party is visibly bored by his presentation, despite the cheerfulness with which he discusses accounting software. He appears again in Telethon giving the same presentation as a part of the Telethon. At the Telethon, everyone is again bored by his presentation, except for Andy Dwyer, who is seen laughing at the puns.
Ben Wyatt applied for a job with Barney's accounting firm in Season 4. Ben was talked out of the job by Jean-Ralphio, who then applied for the job himself. Barney discovered Jean-Ralphio knew nothing about accounting and immediately fired him after he sexually harassed one of the firm's female employees.
Season 5 Edit
In the episode Leslie vs. April Ben is looking for a new job and accepts an offer from Tilton & Radomski. But at the beginning of the first day he quits again, citing that Leslie insists he does something he loves, and he considers helping Tom or taking the various other job offers he has received during the episode.
In "The Cones of Dunshire", Ben Wyatt applies for a job at Barney's accounting firm again after being fired from Sweetums. Barney excitedly shakes hands with Ben, and runs to his coworker, Ted, while shouting, "Ted, he's here! He really came!" Barney is extremely ecstatic that Ben returns and consistently praises him for his work, going as far as throwing a small party that includes Ben's favorite food, calzones. At the end of the episode, however, Ben once again quits his job because he was offered the job as Pawnee's city manager. Barney is disappointed but understands, and he is pleased with Ben's parting gift of the "Cones of Dunshire" game prototype.
Barney later attends the grand opening of Tom's Bistro, where he reveals to Ben that he and the other accountants had copyrighted "The Cones of Dunshire" in Ben's name. He presents the patent as a gift to Ben, who was so pleased that he agrees to come work at the accounting firm, though he recants almost immediately, with Barney calling it the "shortest one yet".
Season 7 Edit
In "Ms. Ludgate-Dwyer Goes to Washington", Andy, Ron and Ben try to convince Barney to hire April at his accounting firm in their quest to find April a job she would like. Ben is clearly attempting to use the influence he knows he has on Barney and the firm with his puns, telling Andy and Ron, "They like me here." Barney is hesitant to hire April, as she has no accounting experience, but numerous persuasion attempts by Andy, Ron and Ben finally get him to decide he'll give her an interview. Right after Barney makes this decision, April calls Ben to tell him she does not want any accounting job. Ben awkwardly tells Barney, "She doesn't want the job," leaving this as essentially the last time Ben has to reject poor Barney and his firm.