Jethro Tull are a British rock band formed in Luton, England, in 1967. Initially playing blues rock and jazz fusion, the band soon incorporated elements of English folk, hard rock, and classical music, forging a signature progressive rock sound. The group’s bandleader, founder, primary composer, and only constant member is Ian Anderson, a multi-instrumentalist who mainly plays flute and acoustic guitar, and is also the lead vocalist. The group has featured a succession of musicians throughout the decades, including significant contributors such as electric guitarist Martin Barre (the longest serving member besides Anderson), keyboardists John Evan, Dee Palmer, Peter-John Vettese, and Andrew Giddings, drummers Clive Bunker, Barrie "Barriemore" Barlow, and Doane Perry, and bassists Glenn Cornick, Jeffrey Hammond, John Glascock, Dave Pegg, and Jonathan Noyce. The band achieved moderate recognition in the London club scene and released their debut album, This Was, in 1968. After a lineup change which saw original guitarist Mick Abrahams replaced by Martin Barre, the band released their folk-tinged second album Stand Up in 1969. Stand Up saw the band achieve their first commercial success, reaching No. 1 in the UK, which was followed by regular tours of the UK and the US. The musical style shifted in the direction of progressive rock with the albums Aqualung (1971), Thick as a Brick (1972), and A Passion Play (1973), and shifted again to contemporary folk rock with Songs from the Wood (1977), Heavy Horses (1978), and Stormwatch (1979). In the early 1980s, the band underwent a major lineup change and shifted towards electronic rock, with the albums A (1980), The Broadsword and the Beast (1982), and Under Wraps (1984). The band won their sole Grammy Award for the 1987 album Crest of a Knave, which saw them returning to a hard rock style. Jethro Tull have sold an estimated 60 million albums worldwide, with 11 gold and five platinum albums. They have been described by Rolling Stone as "one of the most commercially successful and eccentric progressive rock bands." The last works as a group to contain new material prior to their hiatus were J-Tull Dot Com (1999) and a Christmas album in 2003, though the band continued to tour until 2011. Both Anderson and Barre have continued to record and tour as solo artists. Anderson said in 2014 that Jethro Tull "came more or less to an end." The current group—now billed as "Ian Anderson and the Jethro Tull band"—includes musicians who were part of Jethro Tull during the last years of its initial run as well as newer musicians associated with Anderson's solo band, without Barre's involvement. Jethro Tull released The Zealot Gene in 2022 following a gap of 19 years, and are currently working on a 23rd album, titled RökFlöte.