The power system stabilizers (PSS) are widely used for damping out the oscillations in a large power system. The interactions of multiple PSS may adversely affect the system stability, hence, they must be properly coordinated. An optimal control strategy with pseudo-decentralization is proposed for the coordination of multiple PSS. FACTS controllers such as static Var compensator (SVC) and thyristor controlled series compensator (TCSC) are used mostly for improving voltage/reactive power and power flow control. These along with supplementary controllers can also be used for damping out the oscillations in the system. The strategy for coordination of the multiple PSS has also been extended for the coordination of supplementary controllers of SVC and TCSC with PSS. The proposed technique has been tested on 39-bus New England system.