Italian theorist and composer. Became a Franciscan monk, and went to Venice in 1541 to study with Willaert. From 1565 onwards he was maestro di cappella at St Mark's. Though he wrote church music and madrigals (two books of motets survive), he is chiefly important as an outstanding theorist of international influence. His main work, Istitutioni harmoniche (1558), describes the position of excellence reached by music in the High Renaissance (he calls it the ars perfecta) though aware of improvements that could come about through a study of the ancients; he also discusses intervals, modes, word underlay and the art of counterpoint.