The main goal of Fault Tolerant Control Systems (FTCS) is to preserve the ability of the system to achieve the objectives that has been assigned when faults or failures occurred. The main goal of this work is to develop a fault tolerant control strategy that incorporates both reliability and dynamic performance of the system for control reconfiguration. Once a fault has been detected and isolated, the reconfiguration strategy proposed in this paper tries to find possible structures of the faulty system that preserve prespecified performance, calculate the system reliability, compute new controller gains and finally search the optimal structure that has the "best" control performance with the highest reliability. The proposed approach is illustrated through a hydraulic and thermal system of three tanks.