Power system load growth is increasing at a faster rate than the increase in the transmission capability. Transmission congestion occurs when the transmission system is incapable of servicing a load request even if the generation stations are capable of providing it. This paper demonstrates the operation of Thyristor Controlled Series Capacitor for optimization of transmission and thereby, reducing the transmission congestion. A genetic algorithm is developed to optimize a factor, Performance Index (PI) for the contingency analysis, involving both the location and control of TCSC. These devices enhance the transfer capability, minimize the total power loss in a system thereby, improving the system efficiency.