The university is in need of funds and, as a result, the gang is told to attend a fundraiser. At the fundraiser, Leonard meets one of the university's leading donors, Mrs. Latham, and their relationship later takes an intimate turn.
The gang is eating and chatting at the cafeteria, and, unexpectedly, the president of the university, President Siebert, approaches them and asks them to attend a fundraiser for the university. Sheldon refuses to go. On the night of the fundraiser, the gang is ready to go, except Sheldon, who still refuses to go. At the fundraiser, President Siebert approaches the trio and introduces them to Mrs. Latham. Mrs. Latham's condescending attitude terrifies the trio. While Sheldon is video chatting with Amy, she alerts him that if he is not at the fundraiser, the others may fail and the funds will go to other departments including the geology and the liberal arts. Later, Mrs. Latham explains to Leonard that she actually comes to the fundraiser to make smart people feel uncomfortable. Meanwhile, Sheldon is terrorizing the people at the fundraiser.
The following morning, Sheldon gets a phone call from President Siebert telling him to stay away from fundraisers. Next, a phone call comes in for Leonard from Mrs. Latham inviting him out for dinner. After the dinner, Leonard explains how Mrs. Latham is similar to his mother before she suddenly kisses him. After Leonard had arrived home, he explained to the gang what happened at dinner. He also wishes there was something to drink in Apartment 4A. Since they need money for the equipment, Sheldon asks Leonard to proceed with "trading sexual favor for material gain" just like Penny does. And that's a compliment.
The next night, Sheldon gives Leonard a box containing condoms, Viagra, baby oil, and a picture of Mrs. Latham as a 25 year old. Leonard says he won't prostitute himself. On the date, Mrs. Latham expressed her apology for the night before as she made him feel the relationship had taken a Quid Pro Quo turn. She also reassures him that she will be donating the money no matter how this date goes, and after she claims that Leonard would have a night he would not forget with her, he kisses her and presumably, the desperate Leonard hops on the rare opportunity to have sexual intercourse. The next morning, Penny catches Leonard walking the "walk of shame". She enters the apartment and along with Sheldon, she bashes him with a lot of jokes, although Sheldon is serious and tells Leonard he has a knack for gigolo work and should sell himself for more equipment.
At the university, Leonard is showered with applause by President Siebert and his colleagues as he "took one for the team". Siebert also admits that in his earlier days he did the same things Leonard did as a fundraiser.
As credits roll, Howard's voice can be heard asking "So, how was she?"
- Guest starring:
- Teleplay: Chuck Lorre, Eric Kaplan & Steve Holland
- Story: Bill Prady, Lee Aronsohn & Dave Goetsch
- The TV Critic: "I also liked the story being structured to reward Leonard for being agreeable and pleasant. He was rewarded for his social exploits with a big round of applause from his colleagues whereas Sheldon's cold indifference got him banned from future fundraising...Penny laughs at him for it which kind of missed the opportunity to shine a light on their feelings for one another but it was nice just to get an actual ending to a plot for once...This was a good story and the conclusion was passable. Lots of room for improvement but isn't there always?"
- The A.V. Club gave this episode a B.
- IMDb user reviews
- Title Reference: The title refers to the factor that makes Mrs. Latham donate money to the university.
- Chuck Lorre's vanity card.
- This episode was watched by 12.79 million people with a rating of 3.9 (adults 18-49).
- This episode aired in Canada on February 10, 2011 with 3.123 million viewers and a weekly ranking of #2.
- In the United Kingdom, this episode aired on July 14, 2011 with 1.279 million total viewers and a weekly ranking of #6.
- Episode transcript 
- Bernadette is mentioned by name, but is not seen with an appearance in any of the scenes in this episode because Melissa Rauch was not credited to appear as a main cast member in this episode and she wasn't needed for any of the story lines in this episode either
- Leonard received a Dissertation of the Year award for experimental particle physics.
- As Research fellow|senior research fellows in the Department of Physics at the California Institute of Technology, Sheldon, Leonard and Raj have to seek funding for their work, as does Howard, albeit he holds a similar position in the Department of Applied Physics. Other responsibilities for their careers, aside from publishing in Academic journal|peer-reviewed journals, were highlighted in "The Cooper-Nowitzki Theorem" (S2E6), with Sheldon and Leonard having to represent the theoretical and experimental physics divisions for the Graduate school|graduate student research Seminar#Universities|seminar; "The Irish Pub Formulation" (S4E6), wherein Sheldon has to give a thermal fluctuations|thermodynamic fluctuations seminar; "The Thespian Catalyst" (S4E16), in which Sheldon lectures on topological insulators for a graduate course; and "The Contractual Obligation Implementation" (S6E18), at which point Sheldon, Leonard, and Howard serve on a university committee for encouraging more women to pursue a career in the sciences.
- Mrs. Wolowitz picks out Howard's clothes.
- First time that we see President Siebert (he is mentioned in "The Monopolar Expedition":S2E23). He shows up infrequently for the remainder of the series.
- Sheldon says "Hold on. Just because the nice man is offering you candy, doesn’t mean you should jump into his windowless van. What’s the occasion?", but in "The Hook-up Reverberation" (S8E4) the guys have the idea to chip-in some money to help Stuart to re-open the Comic Book Store and later Raj has the idea to get a van and drive around the neighborhood picking up children.
- Co-incidentally, in the first scene of this episode, the films 28 Days Later and Slumdog Millionaire are mentioned, both directed by Danny Boyle.
- Amy is technically engaged to a Saudi Arabia prince, Faisal, who has an interest in neurobiology and paid for her lab. She has a place to stay in Riyadh in the winter.
- Sheldon gives Leonard a bag of items for sex, the prominent coming from the pharmaceutical department, they tell Sheldon it is "to Viagra, what Viagra is to green M&Ms".
- Sheldon, on multiple occasions, refers to Penny as selling her body for favors, while Penny is insulted, Sheldon says he is complimenting her.
- The eighth of nine Season 4 episodes where Melissa Rauch (Bernadette) is absent from.
- The gang is forced into raising money for the physics department.
- Raj: Here's what I wonder about zombies. What happens if they can't get any human flesh to eat? They can't starve to death, they're already dead.
- Howard: You take this one. I spent an hour last night on do how vampires shave when they can't see themselves in the mirror.
- Sheldon: Well-groomed vampires meet in pairs and shave each other: Case closed!
- Sheldon: Tell him Dr. Cooper feels that the best use of his time is to employ his rare and precious mental faculties to tear the mask off nature and stare at the face of God.
- Amy: And consider this, without you to make the case for the physics department, the task will fall to people like Leonard and Rajesh.
- Sheldon: Are you trying to scare me? ‘Cause you’re succeeding.
- Amy: Well, then prepare to be terrified. If your friends are unconvincing, this year’s donations might go to, say, the geology department.
- Sheldon: Oh dear no, not the dirt people!
- Amy: Or worse, it could go to the liberal arts.
Leonard: Are you insane? I'm not going to prostitute myself just so we can get some new equipment!
Sheldon: (disappointed) Oh come on, why not?!
Leonard: Oh... (leaves the apartment and starts walking down the stairs) Goodnight Sheldon!
Sheldon: (also leaves the apartment and begins shouting down the stairs at Leonard, Penny exiting hers partway through) Yeah, given how much time you spend engaging in pointless self-abuse, you might consider just this once, using your genitalia to actually accomplish something!
Penny: Still won't shag the old lady, huh?
Sheldon: No. but thank you for asking.
Leonard: (is stumbling up the stairs carrying his jacket, shirt untucked, hair disheveled. He approaches the door to 4A)
Penny: (exits her apartment dressed to jog and sees the disheveled Leonard and gives him a real-life You-Like-Krabbie-Patties-Don't-You-Squidward look) Good morning, slut!
Leonard: (guiltily grinning and feigning ignorance) What?
Penny: (begins approaching Leonard) Oh please, I know recognize the walk of shame when I see it. All your missing is a little smeared mascara and a purse with panties wadded up in it.
Sheldon: (opens the door wearing a bathrobe) What's going on?
Leonard: (quickly walks past Sheldon) Nothing's going on, excuse me.
Sheldon: Are you just getting home?
Sheldon: (turns to Penny) That's a good sign, right?
Penny: Oh yeah!
Sheldon: (turns back to Leonard with the biggest grin on his face) I'm so proud of you! You sold yourself like a common streetwalker!
Leonard: I didn't do it for the money!
Sheldon: She stiffed you?
Penny: I believe that's what your roommate did to her.
Sheldon: (confused) What?
Penny: Again, read the book we gave you!
Leonard: No, I got the money first!
Sheldon: Smart, get paid up front! you know, I think you have a real knack for gigolo work, Leonard!
- (Leonard enters the cafeteria, which erupts in applause)
- President Siebert: There he is, the man of the hour! (Puts his arm around Leonard's shoulder.) He took one for the team!
- Leonard: I didn't do it for the money.
- Siebert: Keep telling yourself that, it makes it easier. Believe me.
- The Big Bang Theory - The Benefactor Factor (TV Episode 2011) - IMDb
- The TV Critic's Review
- The Big Bang Theory: "The Benefactor Factor" - TV Club - The A.V. Club
- Thursday Final Ratings: 'American Idol,' 'Vampire Diaries' Adjusted Up; 'Private Practice,' 'Bones,' 'Office,' 'Parks & Rec' Down Zap2it
- Top Programs – Total Canada (English) February 7 – February 13, 2011 - BBM Canada
- BARB via Wikipedia