The growth of communication technology over the last decade has been made possible by the significant improvements in the transmission of highspeed data between locations. Today the use of fibre optic and satellite for data transmission has transformed the technology. Electricity supply companies are utilising fibre optics to provide substantial data-carrying capability, for themselves and for third-party use, since the medium provides inherent isolating and insulating properties and immunity to electrical interference, and can be used to advantage alongside existing power networks. This Address charts the development of the techniques used to carry fibre-optic cables alongside existing power networks. It covers the three main methods adopted: embedding fibres within earthwires; wrapping fibres around existing phase or earth conductors; and stringing a separate catenary between towers which carries fibres. It refers to the economics and opportunities of using optical fibres and outlines the methods of installation used to superimpose fibre-optic networks onto existing power systems.