A pioneer of post-punk and industrial hip-hop, he has recorded for On-U Sound Records and Mute Records. Stewart was educated at Bristol Grammar School, one of Bristol's leading private schools, and was in the same year as fellow musician Nick Sheppard. Stewart began his music career in 1977 as a founder of The Pop Group, a band whose sonic experimentation, political conviction, and willingness to collaborate laid the foundations for his later work. The Pop Group split in 1981, with Stewart and two other members heading off to London to hook up with the emerging On-U Sound "conspiracy of outsiders" as part of the New Age Steppers. On-U became a focal point of a diverse set of networks – punks, reggae players from both the UK and Jamaica and free-jazzers. His first post-Pop Group release was as 'Mouth 2', the 1982 single "Who's Hot". Two releases followed with On-U associates under the name 'Mark Stewart & The Maffia' – the "Jerusalem" EP in 1983, and the 1983 album "Learning to Cope with Cowardice". Stewart has since made several albums under his own name as well as collaborating with artists such as Trent Reznor of Nine Inch Nails fame, Tricky, Massive Attack, Chicks on Speed, ADULT. and Primal Scream. In 2005, he released a collection of his best work on Soul Jazz Records entitled "Kiss the Future". Stewart is well known in several European countries and Japan. He recently was involved in a documentary filmed by Tøni Schifer, "On/Off – Mark Stewart – from The Pop Group to the Maffia", which included interviews with Nick Cave, Daniel Miller, former Pop Group members, Adrian Sherwood, Skip McDonald, Doug Wimbish, Keith LeBlanc, Fritz Hart (23 Skidoo) and others. The premiere took place at the East End Film Festival in April 2009. This track record of anarchic pioneering prompted Nick Cave to declare that Stewart as a member of The Pop Group "changed everything". Reflecting on his far-reaching influence, Mark says, "I thought I was making funk music, but a track on Veneer of Democracy supposedly inspired all the American ["Sic"] industrialists, like Front Line Assembly and Skinny Puppy, while another track supposedly inspired the Bristol kids. It happens all the time. I’ve got this nonchalance that nothing is sacred so I’ll crash a Slayer guitar line with Rotterdam gabba beats.