Italian composer, brother of Felice Anerio. He was a choirboy under Palestrina at St Peter's, Rome, and from 1600 held many choirmaster posts in that city at St John Lateran, S. Spirito in Sassia, the Collegio Romano, and S. Maria dei Monti. He also worked for a time at Verona cathedral and his last years were spent directing music at the Polish court; he died on his way back from there to Rome. He published a volume of Masses, several volumes of motets and a collection of psalms, antiphons and litanies; his Teatro armonico (1619) was an important contribution to the development of oratorio, being a collection of laude in dialogue for soloists, choir and instruments. His church music illustrates the transition from a Palestrinian idiom (as in the fine Requiem Mass) to the concertato manner pioneered by Viadana.