David Van Cortlandt Crosby (August 14, 1941 – January 18, 2023) was an American singer, songwriter, and guitarist. He first found fame as a member of the Byrds, with whom he helped pioneer the genres of folk rock and psychedelia in the mid-1960s, and later as part of the supergroup Crosby, Stills & Nash, who helped popularize the California sound of the 1970s. In addition to his music, Crosby was known for his outspoken personality, politics, and personal troubles; he was sometimes depicted as emblematic of the counterculture of the 1960s.

After a short time performing in the folk music scene, Crosby co-founded the Byrds in 1964. They scored their first number-one hit in 1965 with a cover of Bob Dylan's "Mr. Tambourine Man". Crosby appeared on the Byrds' first five albums and the original lineup's 1973 reunion album. In 1968, he formed Crosby, Stills & Nash (CSN) with Stephen Stills and Graham Nash. After the release of their debut album, CSN won the Grammy Award for Best New Artist of 1969. The group later occasionally included Neil Young. The core trio of CSN remained active from 1976 until 2016, and the duo of Crosby & Nash also recorded three gold albums in the 1970s. Crosby, Stills, Nash & Young (CSNY) reunions were held in each decade from the 1970s through the 2000s.

Crosby released eight solo albums, albeit sporadically, over the course of his career. His solo debut was 1971's If I Could Only Remember My Name. The last five of his solo albums, beginning with Croz (2014), came in the last decade of his life. Additionally, he formed a jazz-influenced trio with his son James Raymond and guitarist Jeff Pevar in CPR. He also appeared frequently on recordings by other artists, including Joni Mitchell, Jefferson Airplane, Jackson Browne, James Taylor, Elton John and David Gilmour.

Crosby's combined work with the Byrds and CSNY has sold over 35 million albums. He was inducted into the Rock and Roll Hall of Fame twice: once for his work in the Byrds and again for his work with CSN. Five albums to which he contributed are included in Rolling Stone's list of "The 500 Greatest Albums of All Time", three with the Byrds and two with CSN(Y).

He was also an occasional actor, appearing as a member of Captain Hook's pirate crew in Hook (1991).