Interest in research on nanoscale materials is steadily increasing: nano-structured magnetic materials exhibit new and interesting physical properties, which cannot be found in the bulk. Many of these unique properties have great potential for technical applications in magneto-sensors, bio-sensors, magneto-electronics, data storage, magnetic heads of computer hard disks, single-electron devises, microwave electronic devices, etc. Current research concentrates on device design, synthesis and the characterization of nanostructured materials. The contributions to this book concentrate on magnetic properties of nanoscale magnetic materials, especially on fabrication and characterization, and the physics underlying the unique properties of these structures and devices.