Jason Lee (Buddy/Syndrome) recorded his lines in four days, while Craig T. Nelson (Bob Parr/Mr. Incredible) recorded his lines over the span of two years.
Lily Tomlin was considered for the part of Edna Mode, but turned it down when she heard Brad Bird's vocal performance, saying, "What do you need me for? You got it already."
Helen's use of radio protocol while flying is exceptionally accurate for a movie. In the director's commentary, Brad Bird tells that Holly Hunter insisted on learning the lingo and its meaning. The terminology used hints that Elastigirl has had military flight training. "VFR on top" means she is flying in the regime of Visual Flight Rules "on top" of a cloud cover. She requests "vectors to the initial", directions how to get to the initial landing approach. "Angels 10" is her altitude call, ten thousand feet, this is a military term. Civilian flights use the term "flight level". "Track east" is her direction of travel. "Buddy spike(d)" is a U.S. Military brevity code meaning "friendly anti-aircraft radar has locked on to me, (please don't shoot)." "Transmitting in the Blind Guard" is a call on the emergency frequency where two-way communication has not been established. "Abort" is also a military brevity code, a directive meaning "stop the action/mission/attack." It should be noted that the term "angels", while popular for the first half of the twentieth century, is outdated. As the "present day" story takes place in 1962 and having flight experience clearly took place in the fifties, this is an appropriate term.
Samuel L. Jackson was cast as the voice of Frozone because Brad Bird wanted the character to have the coolest voice.
Brad Bird got the idea for this movie in the early 1990s, basing the story on his own experiences trying to balance a career with family.