Artist specializing in decorative cycles (especially fresco painting) for high-ranking ecclesiastics and Roman princes. He was a favorite of Pope Clement VIII. In Rome his commissions include decoration for the Loggia Orsini, the vault of the Contarelli chapel (S. Luigi de'Francesi), the Capella Olgiati (S. Prassede), and the Palazzo dei Conservatori. He is also noted for designing the mosaics for the dome of St. Peter's. He is typically considered a Late Mannerist artist and his style is sober and clear. His early work is more vigorous and colorful than his later work which is more repetitious.