French composer of sacred polyphonic music, who is believed to have introduced the composition of polyphony in four parts into Western music.

Nothing is known of Pérotin's life, and his identity is not clearly established. He worked probably at the Cathedral of Notre-Dame (Notre-Dame school) in Paris, and his compositions are considered to belong to the Notre-Dame, or Parisian, school, of which he and Léonin are the only members known by name.

Pérotin's four-part works were revolutionary, since religious music of the 12th century was almost entirely in the form of two-part organum (polyphony in which a plainchant melody is sung against another line of music). In Pérotin's organa the liturgical (liturgical music) chant of the tenor is heard against not one voice but two or three voices that provide highly decorative vocalizations. He is known to have composed two four-part works, “Viderunt” and “Sederunt”; another four-part composition, “Mors,” is believed to be his. He also enlarged upon the Magnus liber organi, a collection of organa by his predecessor, Léonin, and made innovations in the use of rhythm. “Viderunt” and “Sederunt,” musical creations comparable in scope to the cathedrals of Gothic architecture, have both been recorded in modern performance.