Circa (stylized as CIRCA:) is a progressive rock supergroup founded by four musicians associated with Yes: current Yes member Alan White (drums), former Yes member Tony Kaye (Hammond, keyboards), current Yes member Billy Sherwood (vocals, bass guitar), and guitarist Jimmy Haun, who played on the Yes album Union.
Since 2012, the lineup has consisted of Sherwood (vocals, guitar), Kaye (keyboards), Rick Tierney (bass guitar), and Scott Connor (drums).