Leftfield is a British electronic project formed in 1989 in London, England. From 1989 to 2002, Leftfield was a duo of artists and record producers that consisted of Neil Barnes and Paul Daley (formerly of the Rivals, A Man Called Adam and the Brand New Heavies). In January 2010, Barnes resurrected Leftfield and having toured the world for a couple of years has finished writing new material for a third album entitled Alternative Light Source. Daley has declined to be involved and is focusing upon his solo career. The duo were hugely influential in the evolution of electronic music in the 1990s with Mixmag describing them as "the single most influential production team working in British dance music". As with many of their contemporaries such as the Chemical Brothers, Leftfield were notable for their use of guest vocalists in their electronic music. Among the more prominent were Toni Halliday on "Original", Johnny Rotten on "Open Up", Djum Djum on "Afro-Left", and Earl 16 and Cheshire Cat on "Release the Pressure". The term progressive house was coined to define their style, a fusion of house with dub and reggae.