Colin Farrell was heavily involved in the look of his character. The comb-over and prosthetic stomach were his idea. He also decided his character would have an obsession with Chinese dragons, and he took part in developing the design for Bobby's apartment.
To promote this film, Warner Bros. Pictures Canada set up a 12-foot voodoo doll resembling a corporate boss in downtown Montreal. People were given the chance to vent their office frustrations on the doll by stabbing and hitting it with large needles. They were also encouraged to share their best or worst boss story for the chance of winning passes to an advance screening of the film.
Jennifer Aniston wore a brown wig to make her character a brunette and more oversexed, a departure from her usual lighter roles.
When looking for a dangerous bar, Gregory claims there is an Applebee's three blocks away. Jason Sudeikis says "those aren't the shitheads we need." Sudeikis would later become the spokesman for Applebee's.
While Director Seth Gordon encouraged most actors and actresses to improvise their lines in various scenes, Jennifer Aniston stated she did not need to because her lines were "beautifully choreographed".