Jethro Tull are a British rock group formed in 1965-1968. Their music is characterised by the songs, vocals and flute work of Ian Anderson, who has led the band since its founding, and guitarist Martin Barre, who has been with the band since 1969. Initially playing blues rock with an experimental flavour, they incorporated elements of classical, folk and 'ethnic' musics, jazz and art rock into their music.