Electric traction is the most favourable type of power supply for electric railways from both ecological and economic perspectives. Its reliability largely depends on contact lines, which must operate reliably in all climatic conditions with as little maintenance as possible. Extreme demands arise when overhead contact lines are required to provide reliable and safe power transmission to electric traction vehicles travelling at speeds in excess of 300 km/h. The authors have used their world–wide experience to provide comprehensive descriptions of configuration, mechanical and electrical design, installation and operation of contact lines for electric railways on local and long–distance transportation systems, including high–speed lines. The book provides students and those embarking on a career in this field with a detailed presentation of the subject, including the electromechanical and structural requirements. Railway company professionals and manufacturers of contact line systems will find practical guidance in the planning and implementation of systems, as well as appropriate specifications and the technical data they will need, including standards and other regulations. Since large sections of the book are dedicated to the system aspects, consultant engineers can also use it as a basis for designing systems and interfaces to other subsystems of electric railway engineering.