Recording all sound on set or on location is the work of the Production Sound Crew which includes Production Sound Mixers, Boom Operators, and Sound Assistants; on bigger films, Sound Trainees may also be employed. Although film is considered a primarily visual medium, much of the storytelling and emotional resonance of a script is conveyed through dialogue.

Ensuring that the dialogue recorded during film shoots is suitably clear is a complex job; most film sets are challenging for the Sound Department as there are often unwanted noises to deal with, or the desired camera shots hamper the placing of microphones.

Although it is sometimes easier to re-record dialogue after the shoot (post-syncing), most actors and Directors prefer to use the sound captured on set or location. Production Sound Crews also record atmosphere (without dialogue) or "wild" tracks on set or on location to assist the Post Production Sound department during the editing process.