The issues of building diagrams of electrical networks, organization and technology for the maintenance and repair of overhead and cable power lines, switchgears and transformer substations are described. Much attention is paid to the feasibility study of the most important areas for improving the operation of electrical networks. The first edition was published in 2005. For students of higher education institutions with a degree in Electric Power Systems and Networks. It can be useful for engineering and technical personnel of electric networks of power systems.