Margaret Thatcher resigned as Prime Minister and leader of the Conservative party in November 1990, but both she and the political ideology to which her name has been appended continue to fascinate pundits and scholars. Indeed, since Thatcher's resignation in November 1990, curiosity about her political legacy has, if anything, increased, fuelled in part by the memoirs produced by the ex-premier herself and a large number of her one-time Cabinet colleagues. Since the early 1980s the bulk of work that has appeared on Thatcherism has been dominated either by what one might describe as the ‘higher journalism’ or by political science scholarship, both of which have been most exercised by the questions of what Thatcherism was and where it took British politics and society. In this essay I want to look at Thatcherism from an historical perspective and thus ask a different question, namely where did Thatcherism, and in particular the political economy of Thatcherism, come from?Given that Margaret Thatcher became leader of the Conservative party in 1975 this might seem a logical starting-point from which to track Thatcherism's origins. Some have argued, however, that Thatcher's election in itself was of little importance, in that the Conservative party's leadership contest in 1975 was a competition not to be Edward Heath, and that Thatcher won because she was more obviously not Edward Heath than anyone else. This emphasis on the personal aspects of the leadership issue necessarily plays down any ideological significance of Thatcher's victory, a point often reinforced by reference to the fact that key elements of the policy agenda that came to be associated with Thatcherism, notably privatisation, were by no means clearly articulated in the late 1970s and did not appear in the Conservative Election Manifesto of 1979.