This is an account of the genesis of Thatcherism in opposition, its record in government, its relationship to the Conservative tradition and the ideological challenge of the New Right. The manner in which Thatcherism has been analysed by the Left and the Right of British politics, and its impact and limits in establishing a new political hegemony and tackling Britain's decline is assessed. Andrew Gamble is author of The Conservative Nation, Britain in Decline, and Introduction to Modern Social and Political Thought.