This book is focused on the spintronic properties of III–V nitride semiconductors. Particular attention is paid to the comparison between zinc blende GaAs- and wurtzite GaN-based structures, where the Rashba spin–orbit interaction plays a crucial role in voltage-controlled spin engineering. The book also deals with topological insulators, a new class of materials that could deliver sizable Rashba spin splitting in the surface electron spectrum. Electrically driven zero-magnetic-field spin splitting of surface electrons is discussed with respect to the specifics of electron-localized spin interaction and voltage-controlled ferromagnetism. The book covers generic topics in spintronics without entering into device specifics, since the overall goal of the enterprise is to provide theoretical background for most common concepts of spin-electron physics and give instructions to be used in solving problems of a general and specific nature. The book is intended for graduate students and may serve as an introductory course in this specific field of solid-state theory and applications.