Rufus McGarrigle Wainwright (born 22 July 1973) is a Canadian-American singer-songwriter.

Wainwright came out as gay while still a teenager. In 1999, he told Rolling Stone that his father recognized his son's homosexuality early on. "We'd drive around in the car, he'd play 'Heart of Glass' and I'd sort of mouth the words, pretend to be Blondie. Just a sign of many other things to come as well." Wainwright later said in another interview that his "mother and father could not even handle me being gay. We never talked about it really."

In addition to his baritone singing voice, he plays both piano and the guitar, often switching between the two instruments when performing live. While some songs feature just Wainwright and his piano, his later work is often accompanied by rock instrumentation or a symphony orchestra, displaying complex layering and harmonies with an operatic feel. Wainwright is an avid fan of opera and Franz Schubert's Lieder. Some of Wainwright's songs have been described as "popera" (pop opera) or "baroque pop". Many of his compositions are densely packed amalgams of strings, horns, operatic choruses, ragtime rhythms, and his own distinctively warm vocal timbre.
He often performs with his sister, Martha Wainwright, on backup vocals. Despite a growing cult following and critical acclaim, Wainwright has experienced somewhat limited commercial success in the United States, although the release of Release the Stars saw increased media attention there, as did the associated 2007 U.S. tour.