Devised theatre (also called collaborative creation, particularly in the United States) is a form of theatre where the script originates not from a writer or writers, but from collaborative, usually improvisatory, work by a group of people (usually, but not necessarily, the performers). This is similar to commedia dell'arte and street theatre such as busking.

It is not always distinguishable from improvisational theatre but by the time a devised piece is presented to the public, it usually has a fixed form: the improvisation is confined to the creation process, and either a writer, a director, or the performers themselves, will have decided exactly what is to be included and the running sequence.

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