Johann Joseph Fux (; c. 1660 – 13 February 1741) was an Austrian composer, music theorist and pedagogue of the late Baroque era. He is most famous as the author of Gradus ad Parnassum, a treatise on counterpoint, which has become the single most influential book on the Palestrinian style of Renaissance polyphony. Almost all modern courses on Renaissance counterpoint, a mainstay of college music curricula, are indebted in some degree to this work by Fux.