Instant Sunshine is an English musical comedy cabaret quartet formed in 1966. Consisting of three doctors from St Thomas Hospital in London—Peter Christie (words and music), David Barlow, and Alan Maryon-Davis (comic asides and sound effects)—the trio added a fourth member in 1972 with journalist and double bass player Miles Kington. In 1998, Kington departed and was replaced by Tom Barlow (no relation to David).
As of 2017, the group recorded five vinyl LPs and were prominently featured on the second and third series of the obscure BBC sitcom One-Upmanship.