John Adair, better known as Johnny Adair or Mad Dog Adair, is an Ulster loyalist drug dealer and the former leader of the "C Company", 2nd Battalion Shankill Road, West Belfast Brigade of the Ulster Freedom Fighters (UFF). This was a cover name used by the Ulster Defence Association (UDA), a loyalist paramilitary organisation. In 2002 Adair was expelled from the organisation following a violent internal power struggle. Since 2003, he, his family and a number of supporters have been forced to leave Northern Ireland by the mainstream UDA.

The UDA West Belfast Brigade is the section of the Ulster loyalist paramilitary group, the Ulster Defence Association (UDA), based in the western quarter of Belfast, in the Greater Shankill area. Initially a battalion, the West Belfast Brigade emerged from the local "defence associations" active in the Shankill at the beginning of the Troubles and became the first section to be officially designated as a separate entity within the wider UDA structure. During the 1970s and 1980s the West Belfast Brigade was involved in a series of killings as well as establishing a significant presence as an outlet for racketeering.