Every year at the U.S. Frontiers of Engineering Symposium, 100 of this country’s best and brightest engineers, ages 30 to 45, have an opportunity to learn from their peers about pioneering work being done in many areas of engineering. The symposium gives early career engineers working in academia, industry, and government in many different engineering disciplines an opportunity to make contacts with and learn from individuals they would not meet in the usual round of professional meetings. This networking may lead to collaborative work and facilitate the transfer of new techniques and approaches. It is hoped that the exchange of information on current developments in many fields of engineering will lead to insights that may be applicable in specific disciplines and thereby build U.S. innovative capacity. Different topics are covered each year, and, with a few exceptions, different individuals participate. The four general topics covered at the 2008 meeting were: drug delivery systems, emerging nanoelectronic devices, cognitive engineering, and countering the proliferation of weapons of mass destruction. The intent of this book is to convey the excitement of this unique meeting and to highlight cutting-edge developments in engineering research and technical work.