Quantum wires are artificial structures characterized by nanoscale cross sections that contain charged particles moving along a single degree of freedom. With electronic motions constrained into standing modes along with the two other spatial directions, they have been primarily investigated for their unidimensional dynamics of quantum-confined charge carriers, which eventually led to broad applications in large-scale nanoelectronics. This book is a compilation of articles that span more than 30 years of research on developing comprehensive physical models that describe the physical properties of these unidimensional semiconductor structures. The articles address the effect of quantum confinement on lattice vibrations, carrier scattering rates, and charge transport as well as present practical examples of solutions to the Boltzmann equation by analytical techniques and by numerical simulations such as the Monte Carlo method. The book also presents topics on quantum transport and spin effects in unidimensional molecular structures such as carbon nanotubes and graphene nanoribbons in terms of non-equilibrium Green’s function approaches and density functional theory.