This work considers the economic policy dinosaurs which apparently went into extinction in the 1980s. They are: the move from "classical" regulation to deregulation; the move from public enterprise to privatization; the move from Keynesian to "monetarist" macroeconomic policy; the shift from rapid growth in government spending and staffing to stabilization and cutbacks; the move from progressive income tax structures towards "flatter taxes"; and the shift from progressive-era public administration to "new public management". None of these major policy shifts were predicted by economists or other mainstream social scientists. The author compares the actual changes with previously established theoretical accounts of what makes policy shift and explores how far the changes can be understood in terms of the power of ideas, the power of interests, the effect of changing social contexts and "self-destructive" dynamics of public policy.