A tie-in work is a work of fiction or other product based on a media property such as a film, video game, television series, board game, web site, role-playing game or literary property. Tie-ins are authorized by the owners of the original property, and are a form of cross-promotion used primarily to generate additional income from that property and to promote its visibility.

A novelization is a derivative novel that adapts the story of a work created for another medium, such as a film, TV series, stage play, comic book, or video game. Film novelizations were particularly popular before the advent of home video, but continue to find commercial success as part of marketing campaigns for major films. They are often written by accomplished writers based on an early draft of the film's script and on a tight deadline.