A novel model-following approach is developed to design reconfigurable control systems. The conventional state-space linear model-following approach to control is first re-examined with emphasis on the conditions for perfect model following and its application to reconfigurable control system design. New frequency domain necessary and sufficient conditions for perfect model following are then obtained and they are used to gain insight into the selection of the reference model and to develop a new design approach. This novel design approach yields fewer constraints on the reference model than before, and provides much greater flexibility in specifying the state trajectories of the impaired system.