This book provides a comprehensive review of the present knowledge and current problems concerning physical-chemical aspects of the behavior of excess electrons in various media. The book's 13 chapters strike a balance between theoretical and experimental accounts and provide in-depth presentations of specific subjects. Among the several topics discussed in this stimulating volume are primary interactions, transport, and relaxation of excess electrons of a few tens of electron-Volts in various solid and liquid materials; energetics and transport properties of electrons after thermalization in non-polar dielectric liquids; quantum simulation methods; and electron solvation in polar liquids and of excess electrons trapped in polar matrices at low temperature. Applications of these concepts are discussed as well, including hot electron transport in silicon dioxide, the fate of excess electrons created in polar dielectric liquids by photoelectrochemical methods or by cathodic generation, and excess electron production and decay in organic microheterogeneous systems. Researchers, instructors, and engineers working in the radiation sciences, condensed-matter physics, chemical physics, biophysics, photochemistry, and the biochemistry of electron transfer and electrochemistry should consider this book to be an invaluable reference resource.