The Presbytery, used by the monks of Ewenny Priory for their daily round of Offices and Mass, is distinctive in 12th century architecture in having three bays and two differnt styles of vaulting to the ceiling, barrel-vaulting for the first two, and crossed-rib vaulting for the eastern-most over the altar. The vaulting and low ceiling provided excellent acoustics for the monks as they sung their offices.