This book gives the solution for a long known and, in the professional and scientific circles, not seldom mentioned problem ? how one can determine mutual, inductive influence between an electric power line and metal installations surrounding this line in urban and/or suburban areas. The method presented in this book enables the compensation of the objective deficiency of the necessary data about the surrounding metal installations through the field measurements. The calculative part of the method is based on introduction of a fictitious conductor which is equivalent, from the standpoint of the inductive effects, to all actually existing surrounding metal installations. Physical appearance of this conductor is assumed to be a cylinder enveloping all conductors of the considered power line along its entire length. The book is assigned for the use of professionals involved in the design and exploitation of distribution network, but also is recommended to the academic people: professors, postgraduates, graduated and students of electrical engineering.