Koyaanisqatsi is a 1982 American non-narrative documentary film directed and produced by Godfrey Reggio, featuring music composed by Philip Glass and cinematography by Ron Fricke. The film consists primarily of slow motion and time-lapse footage (some of it in reverse) of cities and many natural landscapes across the United States. The visual tone poem contains neither dialogue nor a vocalized narration: its tone is set by the juxtaposition of images and music. Reggio explained the lack of dialogue by stating "it's not for lack of love of the language that these films have no words. It's because, from my point of view, our language is in a state of vast humiliation. It no longer describes the world in which we live." In the Hopi language, the word koyaanisqatsi means "life out of balance".

It is the first film in The Qatsi Trilogy, which was followed by Powaqqatsi (1988) and Naqoyqatsi (2002). The trilogy depicts different aspects of the relationship between humans, nature and technology. Koyaanisqatsi is the best known of the trilogy and is considered a cult film. However, because of copyright issues, the film was out of print for most of the 1990s. In 2000, the film was selected for preservation in the United States National Film Registry by the Library of Congress for being "culturally, aesthetically, or historically significant".