For the past twenty years, the primary goal of American energy policy has been to reduce the nation's reliance on oil, but, according to Pietro S. Nivola and Robert W. Crandall, policymakers have been going about it inefficiently in the transportation sector. They say the United States, rather than continuing to administer mileage mandates on motor vehicles, should raise the price of motor fuel to moderate consumption. The authors find that an additional excise of twenty-five cents a gallon over the past nine years would have conserved at least as much oil as the existing policy of imposing gas mileage requirements for new passenger vehicles. And such a tax, they contend, would not be as detrimental to the economy as opponents fear, nor as regressive as they claim. The authors examine the development of motor-fuel excises in Great Britain, France, Germany, Japan, and Canada, explaining the historical and political factors that have led to different national policy orientations. Turning their attention back to the United States, Nivola and Crandall show how regulatory measures have fallen short of their goal and why political barriers to bolder taxation of gasoline remain formidable. They conclude by offering suggestions for new directions in U.S. policy at the federal, state, and local levels.