This book contains a collection of papers giving insight into the fundamentals and applications of nanoscale devices. The papers have been presented at the NATO Advanced Research Workshop on Nanoscale Devices – Fundamentals and Applications (NDFA-2004, ARW 980607) held in Kishinev (Chisinau), Moldova, on September 18-22, 2004. The main focus of the contributions is on the synthesis and characterization of nanoscale magnetic materials, the fundamental physics and materials aspects of solid-state nanostructures, the development of novel device concepts and design principles for nanoscale devices, as well as on applications in electronics with special emphasis on defence against the threat of terrorism.