Over the past five years, the Department of Energy’s Office of Basic Energy Sciences has engaged thousands of scientists around the world to study the current status, limiting factors and specific fundamental scientific bottlenecks blocking the widespread implementation of alternate energy technologies. From these efforts, it becomes clear that the magnitude of the challenge is so immense that existing approaches will not be enough to secure our energy future. Instead, meeting the challenge will require fundamental understanding and scientific breakthroughs in new materials and chemical processes to make possible new energy technologies and performance levels far beyond what is now possible. This book discusses and identifies strategic goals for which transformational scientific breakthroughs are urgently being researched for tomorrow’s energy needs.