Thijs van Leer is a Dutch singer and keyboardist, best known as the founding member of the rock band Focus as its primary vocalist, keyboardist, and flautist. Born and raised in Amsterdam among a musical family, van Leer took up the piano and flute as a child and pursued them at university and music academies.

Focus is a Dutch progressive rock band formed in Amsterdam in 1969 by keyboardist, vocalist, and flautist Thijs van Leer, drummer Hans Cleuver, bassist Martijn Dresden, and guitarist Jan Akkerman. The band has undergone numerous formations in its history; since December 2016, it has comprised Van Leer, drummer Pierre van der Linden, guitarist Menno Gootjes, and bassist Udo Pannekeet. They have sold one million RIAA-certified albums in the United States.