Many of the scenes in the forest are allusions to or recreations of scenes in the Björk music video "Human Behavior", also directed by Michel Gondry.
The studio originally wanted Spike Jonze to direct the film because of the success of Being John Malkovich (1999). He considered it, but opted to produce, and suggested Michel Gondry, instead.
In a 2014 interview, body double actress Laura Grady talked about doubling for Patricia Arquette. "I had a part in that where I played one girl who was naked onscreen, and then I was also Patricia Arquette's body double. I remember Rhys Ifans being very shy. It's really funny -- when you work with another body double, we're laughing about stuff, like we're waiting tables. But when you work with the actor, they get so shy. They think because I'm a body double, that I do it all the time, that I'm not shy -- but of course I am a little bit!"
Steven Soderbergh was first interested in directing Charlie Kaufman's script back in late 1996, when Kaufman was still trying to get Being John Malkovich (1999) produced. Soderbergh's considerations for casting were for David Hyde Pierce in the role of Nathan Bronfman, Chris Kattan in the role of Puff (likely due to his character Mr. Peepers on Saturday Night Live (1975) at the time), and Marisa Tomei in the role of Lila Jute. He was about to go into pre-production when he was offered Out of Sight (1998) and after much deliberation he left the project.
To put herself in the shoes of her character, Patricia Arquette had to endure having human hair stick to her body, which prevented her from sitting between takes. She also suffered from poison ivy while filming around Los Angeles. But the worst part, what she had to endure being naked for hours. Arquette says, "there were a lot of young people on the tech team, so I was running naked in the forest and all of a sudden I met outdoor enthusiasts out for a walk. I almost went to see the technicians to tell them, 'Guys, you had to close access to the filming locations. What are you doing? I'm naked here!' People were taking pictures of the ferns and suddenly they were screaming: 'Look, it's Patricia Arquette running naked!'"