Stanley Kubrick worked on the project for two decades before his death, but along the way, he asked Steven Spielberg to direct, saying it was "closer to his sensibilities." The two collaborated for several years, resulting in Kubrick giving Spielberg a complete story treatment and lots of conceptual art for the movie prior to his death, which Spielberg used to write his own scenario. Contrary to popular belief, Spielberg claims he introduced many of the darker elements into the story, while Kubrick's main contribution consisted mostly of its "sweeter" parts. In a 2002 interview with movie critic Joe Leydon, Spielberg indicated that the middle part of the movie, including the Flesh Fair, was his idea, whereas the first forty minutes, the Teddy bear, and the last twenty minutes were taken straight from Kubrick's story. Ian Watson, who wrote Kubrick's original treatment, confirmed that even the much-criticized ending, assumed by many to be a typical Spielberg addition, was "exactly what (he) wrote for Stanley, and exactly what he wanted, filmed faithfully by Spielberg."
The list of words that Monica Swinton (Frances O'Connor) says to David (Haley Joel Osment) to make him capable of love was the original list, written by Stanley Kubrick.
It was Stanley Kubrick's idea to include industrial metal band "Ministry" to the movie. He was a big fan of them, and called lead singer Al Jourgensen asking him if he would like to be in the movie, Al, assuming it was just a prank, hung up on him.
This movie also pioneered the virtual studio, a technique which allowed director Steven Spielberg to walk through a virtual version of Rouge City with his camera and select shots. This technique was used on The Lord of the Rings trilogy.
Real-life amputees played some of the robots with missing limbs.