Although politicians promise innovation and change when they run for office, once elected they face inherited commitments to programmes initiated by their predecessors, legacies that severely limit their freedom of choice. In this work, Richard Rose and Philip L. Davies systematically examine the ways in which decisions made by past generations of administrators control policy-making in the present. Basing their conclusions on a unique study of hundreds of public programmes in effect in Britain since 1945, Rose and Davies show that the impact of an administration's choices is greatest long after its term is concluded. Thus, the impact of the Thatcher government's choices will be felt in the next Parliament, and in Parliaments after the year 2000. Even though individual politicians have left office, their agenda is carried forward by the fabric of political inertia - the laws, public agencies, and budgets in continuing effect and the expectations of beneficiaries. The limited choices that each administration makes are of two very different types. Some reflect careful deliberation over the years and are incorporated in the legacy of successive administrations. Others are trial-and-error attempts to deal with dissatisfaction arising from conditions that often lead to failure. The authors test three theories to account for differences in the persistence of particular types of policy. They conclude that the biggest stimulus for choice (and failure) comes from the turbulence of the market. Social programmes are adopted much less often but are much more durable because they concern the enduring needs of families.