David Van Cortlandt Crosby is an American singer-songwriter and guitarist. In addition to his solo career, he was a founding member of both the Byrds and Crosby, Stills& Nash. Crosby joined The Byrds in 1964. The band gave Bob Dylan his first number one hit in April 1965 with "Mr. Tambourine Man." Crosby appeared on the band's first five albums, and produced the original lineup's 1973 reunion album.