The show had to stop production in November 2007 because of a writer's strike. The show's star Steve Carell (himself a WGA member) supported the writers, and refused to cross the picket lines even for non-writing duties. Carell went so far as to call in sick to the network on the first day of the strike, citing a case of "enlarged balls" as the reason he couldn't come in.
Paul Lieberstein's role as Toby Flenderson was meant to be a one-time appearance, since Lieberstein had never acted before, and never actually wanted to because of his quiet, reserved personality. However, NBC President Kevin Reilly saw the episode where Toby appeared and reportedly said "That red-haired guy is terrific, we should see more of him." Toby then became a recurring character, and the cast and crew have repeatedly lavished praise on Lieberstein's acting abilities, and he has allowed the role to expand somewhat while remaining abashed by the attention it's brought to him. Notably, Toby has no or few lines or story presence in any episode that Paul Lieberstein writes or directs.
Steve Carell only watched a few minutes of the British version before permanently stopping such viewing because he did not want to copy Ricky Gervais' performance as the office manager. John Krasinski, on the other hand, was an avid viewer of the original.
Some of the video used in the opening theme song specifically the exterior shot of the building was taken by John Krasinski and his friends in their Jeep. John had just gotten the part and was coming out for shooting.
The first season was filmed in actual office space located just above a sound-stage. The sound-stage is often used to replicate the Dunder-Mifflin warehouse, most notably in the "Basketball" episode. For the second season, an exact set replica of the original office was built on a sound-stage for further shooting.
Dwight states that Jim Halpert "looks like the world's tallest hobbit". The character of Jim is based upon Tim Canterbury from the original UK version, Tim was played by Martin Freeman, who would go on to play Bilbo Baggins in The Hobbit: An Unexpected Journey (2012).
It is frequently mentioned that the characters Phyllis Lapin Vance and Michael Scott are the same age, having gone to high school together. In real life Phyllis Smith is 11 years older than Steve Carell.
All the principal characters have had their full names revealed throughout the series. Michael Gary Scott; Dwight Kurt Schrute III; James "Jim" Duncan Halpert; Pamela "Pam" Morgan Beesly; Ryan Bailey Howard; Andrew "Andy" Baines Bernard (Born Walter Jr.); and Angela Noelle Martin.
Michael Scott's home address is shown as either 42 Kellum Court (per NBC's Dunder Mifflin website) or 126 Kellum Court (seen on the show). Kellum Court is a real street in Scranton, but house numbers start at 300 because of the city block numbering system. If it existed, the physical location of 42 Kellum Court would actually be in the rock quarry depicted behind the "Scranton Welcomes You" sign in the opening credits.
Many main and supporting cast members have written episodes of the show. B.J. Novak (Ryan), Paul Lieberstein (Toby) and Mindy Kaling (Kelly) wrote 12 of the 28 episodes over the first and second seasons (albeit separately). (Liberstein would even go on to direct a fourth season episode, "Money".) Steve Carell (Michael Scott) has written two episodes so far: "Casino Night" (which was the second season finale) and "Survivor Man". One episode (2.8, "Performance Review") was written by Larry Wilmore, who plays Mr. Brown, the diversity instructor. Michael Shur, a seasoned writer, plays Dwight's cousin Mose Schrute. Gene Stupinsky and Lee Eisenberg, two writing partners, play the delivery men in the Valentine's Day episode and others. Greg Daniels, the developer and show runner of the Office, played Michael's neighbor in "Office Olympics" but his scene was cut.
The "Welcome to Scranton" sign featured in the opening credits, formerly located on the Central City Expressway, is now on display in the food court of the Mall at Steamtown. It is setup with a backdrop so people can get their picture with it. It was moved there when the city replaced the signs with new signs.
Many of the famous insert shots from the original series such as the water cooler and copier machine are not used in the show. Instead they pay homage to those particular shots by placing them in the opening credits.
NBC.com sends out bobble head coupons on character birthdays. They have sent one out on Michael's, Jim's, and Pam's birthdays. This reveals that Michael was born on March 15, 1964; Jim- October 1, 1978; Pam- March 25, 1979.
The exterior shot of the building the office is "in" in Scranton, Pennsylvania is across the street from a bar which is coincidentally named "The Office". Greg Daniels has said that he hopes this is a sign of good karma for the show. The Office (the bar) was actually condemned by the city a few years back.
Four of The Office cast members were interns on Late Night with Conan O'Brien (1993): Angela Kinsey in 1993, Mindy Kaling in the winter of 1999, John Krasinski in summer of 2000, and Ellie Kemper in spring of 2005.
Originally, after the show was first picked up, NBC planned on retitling the series "The American Workplace" in order to differentiate it from the original British version. The idea was later scrapped.
There are some changes in the set between the first season and the subsequent ones. The exterior of the building is completely different in the first season than what's used after. Also, the wall in between Michael's office and the conference room (the one Andy punches a hole in) is much thinner in the first season. Also in the first season there is a door to the left of the break room door that disappears, and above Creed and Merideth's desks. Now there is just a door between Creed's desk and Oscar, Kevin's, and Angela's island.
Dwight has a "Froggy 101" bumper sticker on the filing cabinet next to his desk. Froggy 101 is the #1 rated country-western station in Scranton, Pennsylvania, the setting for the show. This bumper sticker can also be seen in the office of Michael's boss at his short-lived night job at the telemarketing company.
Dwight currently has four bobble-heads on his desk. The most well known is the "Dwight Schrute" bobble-head, a present from Angela in season two. Two others seen throughout the series are of Mike Lieberthal and John Kruk. Lieberthal played catcher for the Scranton/Wilkes-Barre Red Barons before being promoted to the Philadelphia Phillies and John Kruk was a Philadelphia Phillie before retirement. The fourth bobble-head, added in the fourth season, is of former Syracuse University guard and Scranton native son Gerry McNamara.
First ever NBC comedy series on NBC to be presented in wide-screen to non-HDTV viewers, resulting in horizontal black bars. Previous NBC dramas have been presented in wide-screen to non-HDTV viewers, but no previous comedy.
Four of the main cast members are originally from Massachusetts: Steve Carell (Michael Scott), John Krasinski (Jim Halpert), B.J. Novak (Ryan Howard) & Mindy Kaling (Kelly Kapoor). Guest stars Nancy Walls (Carol Stills), Steve Carell's real-life wife and Andy Buckley (David Wallace), are also from Massachusetts.
The Penn Paper building featured in the opening credits is located at 215 Vine Street in Scranton, PA, which is about one block from Mifflin Ave. This is likely where the fictional company name "Dunder Mifflin" came from. The "Penn Paper" sign on the building has now been replaced by "PA Paper" in blue lettering.