Music and politics have long been connected. One of the most recent examples was Live 8 in July 2005, when a series of concerts was used to put pressure on G8 leaders to change their policy on third world debt. While the connection is often observed, it is rarely analysed in any detail. This article is an attempt to provide some of that detail. It begins by asking whether participating in music can also mean participating in politics. It goes on to explore the conditions that are necessary for this conjunction of politics and music. It does this by comparing two UK examples of music-based political movements, Jubilee 2000 (which culminated in Live 8) and Rock Against Racism. It ends by arguing that the link between politics and music has to be understood along three dimensions: the organisation of the link, its legitimation and its cultural performance.