Pollution flashover accidents in H.V. insulators had a great assessment in power outage of transmission lines. Two new techniques using artificial neural networks are presented in this book to monitor the discharging level on the insulator surface. The techniques can be programmed to a monitor that produces an alarm signal when the discharging level reaches dangerous range and hence it can be used to predict the flashover accidents before its occurrence.The new techniques using instantaneous leakage current patterns and the meteorological effects are used to classify the discharging activity on the insulator surface and to produce early alarm before insulator flashover occurrence. Thus online monitoring systems using these techniques lead to early prediction of H.V. insulators flashover due to pollution accidents. The new techniques can be programmed to a digital online monitors’ hardware proposed as a schematics for future work in this book. The new online monitor can predict many flashover accidents in power systems and therefore save a lot of power lost due to flashover accidents faults on H.V. insulators.Also the electrical power system stability will be improved .