Martin Lancelot Barre (/bɑːr/; born 17 November 1946) is an English guitarist best known for his longtime role as lead guitarist of British rock band Jethro Tull, with whom he recorded and toured from their second album Stand Up in 1969 to the band's initial dissolution in 2011. In the early 1990s he began a solo career, and has recorded several albums as well as touring with his own live band.
He has also played the flute and other instruments such as the mandolin, both on stage for Jethro Tull and in his own solo work.