Zinc Oxide (ZnO) is a metal oxide semiconductor of group II-IV whose nature resides at the borderline between covalent and ionic semiconductors. In the last decade it has raised several attention in the research field since it possesses promising catalytic, electrical, electronic and optical properties. It can be easily prepared in different shapes and sizes at both the micrometric and nanometric scale, including the forms of micro- and nanowires, nanobelts, nanotubes, micro- and nanoparticles, multipods, tetrapods, and flower-like microstructures. This different variety of morphologies has thus attracted considerable attention for potential application in solar cells, nanogenerators, field effect transistors, gas sensors and other electronic micro- and nanodevices. This book discusses the synthesis and the electrical properties of ZnO nanowires. It also discusses rough silver nanowires, nanobuds and nanoparticle substrates; the synthesis and properties of Ni nanowires in porous silicon templates; and phonon scattering and elastic energy propagation in nanowires.