This 2013 Edition of the Institute for 21st Century Energy ‘s Index of U.S. Energy Security Risk (U.S. Index) illustrates, perhaps more than any of the previous editions, the scale and scope of the changes taking place in U.S. energy markets and how those are improving energy security at a pace unseen since the early 1980s. It also is a good time to take stock of how the U.S. Index, after four editions, has done at answering the simple question: Is our energy security is getting better or worse, and why?