It takes Rob 11½ months to write, direct and shoot 15 episodes of It's Always Sunny In Philadelphia.
Rob along with Danny DeVito rang the opening bell for the Philadelphia Stock Exchange on the 6th June 2007.
People often joke about Rob looking like the The Sixth Sense actor Haley Joel Osment, and often ask if sees dead people.
Rob starred as himself in a short feature titled Danny DeVito & The Contract on the 27th August 2007, also starring as themselves are Danny DeVito, Charlie Day, Fred Savage and Rhea Perlman.
Rob was interviewed on the FOX television show Life After Film School (Season one, Episode 19) which aired on 9th September 2007.
Rob starred in a television commercial for Nike in 1999.
Rob's favourite bands/artists are Avenged Sevenfold, System of a Down, Pink Floyd, Metallica, The Eagles and The Pixies.
Rob met with 'Lost' co-creator and executive producer Damon Lindelof who was a fan of 'It's Always Sunny in Philadelphia', and offered to give Rob a small role in as Aldo in the season three episode 'Not In Portland'.
McElhenney made his film debut in 1997 with a bit part as Kevin in 'The Devil's Own' and followed that up with bit parts in 'A Civil Action' and 'Wonder Boys'. He later had more substantial parts in 'Latter Days' and 'The Tollbooth'.
Rob attended St. Joe's Preparatory school in Philadelphia. His character Mac and Charlie also attended the school on the show.
Even after It's Always Sunny in Philadelphia was picked up by FX, Rob was running low on money and had to continue his previous job as waiter at nights for a while.
Rob along with his friends and co-stars Charlie Day and Glen Howerton shot the pilot of It's Always Sunny In Philadelphia with a budget of less then $200, including food. Rob wrote the script and they edited it on their computer.
Like the characters Mac, Charlie and Dennis on It's Always Sunny in Philadelphia creator/writer Rob McElhenney attended St. Joe's Prep in Philadelphia.
In August 2005 Amy Amatangelo of the Boston Herald made this prediction: "Where you'll see him in five years: making an Academy Award-winning film for less than $2,000."
On how he is like his character, Rob McElhenney has said: "It's all sort of autobiographical in as far as we take the darkest parts of our personalities and put them on screen. I'm amazed at how many people will come up to me and say how they were thinking a lot of the things that I was saying on the show and how much they relate to my character, and I'm like, `My character is one of the worst human beings on the planet.' "
He dropped out of Temple University after one semester to pursue his acting career.
Rob: (On the creation of Boldly Going Nowhere) We grew up watching shows like Star Trek, anything having to do with the future, and it was always about the adventures they'd go on, We thought it would be funny to watch what goes on in between those adventures, when they're waiting for the next big thing to happen. How do they keep themselves busy?
Rob: (On his meeting with Danny DeVito) The meeting was official. But he lived next to Brad Pitt and Jennifer Aniston while they were getting divorced. There were people everywhere taking pictures. Danny didn't have any stalkers, so I was the one guy stalking Danny.
Rob: (On his It's Always Sunny In Philadelphia character Mac) Mac is exceptionally vain, in fact the entire Gang is, Mac works from a pathetic place of insecurity. These people are uneducated, unmotivated and just live to just get one over each other.
Rob: (On networks looking for good material) Everybody out here in Hollywood is looking for good material. Everybody wants the next best thing, and they don't care if it's Steven Spielberg bringing it to them or if it's Sally O'Brien living in Cleveland. All they care about is the material. The creative people are now doing what they do and then going right to the networks, right to the studios. And if it's funny, somebody will put it on the air.
Rob: (On FX network shows he likes to watch) 30 Days is an amazing show, I met Morgan Spurlock at one of the FX things, he's awesome. This summer too, I watched The Riches, that was really good too.
Rob: (On talk shows) They want to see tape on you. They want to know you're not going to just come on their show and be a drag. I can understand that. It's just hard to promote our show unless they invite us on. However, Danny is going to do The View again and we're going to be on that.
Rob: (On getting rid of his South Philadelphia accent) [voice drops] Oh yeah, yeah, I got ridda it a long time ago. People'd ohways ask me, when I ask them for wudder, they'd be like, whadderya talkinabout? [back to Hollywood voice] I started doing commercials, and they said, "Look, we want to hire you, but you sound like a hood. People in Iowa are not going to want to buy butter from a guy like you. You gotta drop the tough-guy routine." I was like, "I'm not a tough guy!"
Rob: (On being cut out of movies) I was cut out of a lot of movies. My first job was The Devil's Own. I had a scene with Harrison Ford and a scene with Brad Pitt, and I was like, this is amazing! Then I got cut out of the entire movie. It happened again in Wonder Boys. I played opposite Katie Holmes, and I was her boyfriend. I got cut out of that, too.
Rob: (On meeting Fred Savage) Honestly we met with him solely because he was Fred Savage, and we thought it would be cool to talk to this guy about The Wonder Years. But he came in with extensive knowledge of our show. an incredible energy and attitude. And we just said 'Man, this guy would be perfect'.
Rob: (On the song 'Day Man') Day Man has been huge, and we really want to take advantage of that. We're really happy that people seem to dig that. We are thinking about doing a Day Man/Night Man rock opera, in the vein of Tommy. The whole show wouldn't itself be a musical, but we'd perform a musical within the episode, so that way you can see us in between. Maybe it's the story of how Day Man came to be the ruler of the universe.
Rob: (On how he got into acting) I went to the Prep and then straight to New York City. I enrolled in acting classes and really took to it. I'd been involved in a couple of school plays. I did one at Notre Dame Academy, but that was just to meet girls.
Rob: (On what Rob and the cast think about It's Always Sunny In Philadelphia) We feel we're amongst the funniest if not the funniest show on television, and let's see what happens when we go up against the networks.