Power system is always affected by transients that create oscillations & voltage instability. Several techniques are invented to overcome instability problems & improve power system performance. The most common used technique is Power System Stabilizer called PSS. The PSS has limit to damp the oscillations due to power grid network. So another device/stabilizer is required for system stability & reliability. These requirements generate the vacancy for FACTS & FACTS devices like SSC, IPFC, UPFC, SVC & STATCOM. In this paper, the authors used TCSC as controller for stability of power system & tuning of TCSC is done by the genetic algorithms.