How America can look within to achieve energy security and reduce global warming

The American Physical Society regularly produces reports on issues of public import that require technical understanding and for which an objective and authoritative analysis would be of particular use to the public and policy makers. This report, entitled Energy Future: Think Efficiency, is the latest in the series and appears here as a special supplement issue of Reviews of Modern Physics, as have other such reports. It is hard to imagine a more timely study topic, given the urgent environmental, geopolitical, and economic incentives for improving energy efficiency at this juncture. Energy Future: Think Efficiency provides a valuable and broadly applicable guide to effective approaches, many of which employ existing technologies and, surprisingly, need not be difficult or expensive. In order to have the most immediate impact, an earlier version of Energy Future: Think Efficiency was issued at a press release in Washington, D.C. in September of 2008 in hard copy and online. Prior to its release a distinguished review panel examined the report and its conclusions. Thus the study has been rigorously refereed although this was outside of the usual review process employed by RMP. Except for adjustments in pagination, this version is unchanged from the earlier version. The report introduction contains full information on the study personnel, review panel members, and other acknowledgments, so these are not repeated here. What is repeated is an expression of deep appreciation to all those involved in the preparation of a revelatory report on a topic of critical importance.