Karan Johar had written the script with his friend Kareena Kapoor in mind as the leading lady. But she asked for too high a fee and was replaced by Preity G Zinta.
Unlike many other Bollywood productions, the filmmakers actually complied with international copyright laws and bought the license to the rights to Roy Orbison's "Pretty Woman," which is featured in the film.
Portions of the film were shot in Toronto because of escalated production costs from filming in New York City.
In the beginning Naina is supposedly running, but Preity G Zinta had fallen and injured herself. Nikkhil Advani got a model to jog in front of the camera instead.
Abhishek Bachchan and Vivek Oberoi were approached for Saif Ali Khan's role.