The practice of engineering is continually changing. Engineers today must be able not only to thrive in an environment of rapid technological change and globalization, but also to work on interdisciplinary teams. Cutting-edge research is being done at the intersections of engineering disciplines, and successful researchers and practitioners must be aware of developments and challenges in areas that may not be familiar to them. At the U.S. Frontiers of Engineer Symposium, engineers have the opportunity to learn from their peers about pioneering work being done in many areas of engineering. Frontiers of Engineering 2011: Reports on Leading-Edge Engineering from the 2011 Symposium highlights the papers presented at the event. This book covers four general topics from the 2011 symposium: additive manufacturing, semantic processing, engineering sustainable buildings, and neuro-prosthetics. The papers from these presentations provide an overview of the challenges and opportunities of these fields of inquiry, and communicate the excitement of discovery.