Despite recent reforms, world agricultural markets remain highly distorted by government policies. Traditional indicators of those price distortions can be poor guides to the policies? economic effects. Recent theoretical literature provides indicators of trade and welfare-reducing effects of price and trade policies which this paper builds on to develop more-satisfactory indexes. The authors exploit a new Agricultural Distortion database to generate estimates of them for developing and high-income countries over the past half century. These better approximations of the trade and welfare effects of sector policies are generated without a formal model of global markets or even price elasticity estimates.