A large portion of the original footage (including the wedding itself) was ruined by an airport x-ray machine. The scenes had to be re-shot, when additional funds had been raised to do so, some months later.
In one scene, Deubey-ji is on a scaffolding and speaking on the phone. He climbs around and has an amusing conversation which concludes with him noting that the signal was better on the ground then on the scaffold. The entire scene, with its intricate monologue and movement, was improvised by Vijay Raaz, the actor who played Dubey. Source: Director Mira Nair in a talk at Emory University.
The photo of Surinder (Lalit's late brother), was actually a picture of a friend of Mira Nair who had recently died.
The movie won the Golden Lion, the highest prize at the Venice Film Festival 2001. Mira Nair was the second Indian (after Satyajit Ray for L'invitto (1956)).
Lillete Dubey (Pimmi Verma) and Neha Dubey (playing Ayesha Verma) are mother and daughter in real life.