The monograph shows the influence of neutral modes on the most important performance indicators of electrical distribution networks of various voltages. The basic principles of operation of networks with isolated, grounded through active resistance, effectively grounded neutral and with compensation of capacitive currents of ground closure. The principles of automatic regulation of inductance of reactors are described . Designs of earthing devices of active resistances, arc-extinguishing reactors with variable gap, magnetization, thyristor switching of turns, etc. are presented. Considerable attention is paid to the theory, calculation and methods of preventing ferro-resonance processes occurring in networks under adverse neutral mode. Requirements for selective relay protection and signalling of ground circuits in electrical networks depending on neutral modes. are considered. For scientific and engineering workers engaged in the field of electricity.