Real-time hybrid simulation is an attractive method to evaluate the response of structures under earthquake loads.The method is a variation of the pseudodynamic testing technique in which the experiment is executed in real time,thus allowing investigation of structural systems with rate-dependent components.Real-time hybrid simulation is challenging because it requires performance of all calculations,application of displacements,and acquisition of measured forces,within a very small increment of time.Furthermore,unless appropriate compensation for actuator dynamics is implemented,stability problems are likely to occur during the experiment.This paper presents an approach for real-time hybrid simulation in which compensation for actuator dynamics is implemented using a model-based feedforward compensator.The method is used to evaluate the response of a semi-active control of a structure employing an MR damper.Experimental results show good agreement with the predicted responses,demonstrating the effectiveness of the method for structural control performance assessment. Real-time hybrid simulation is an attractive method to evaluate the response of structures under earthquake loads. The method is a variation of the pseudodynamic testing technique in which the experiment is executed in real time, thus allowing investigation of structural systems with rate-dependent components .Real-time hybrid simulation is challenging because it requires performance of all calculations, application of displacements, and acquisition of measured forces, within a very small increment of time. Futuremore, unless appropriate compensation for actuator dynamics is implemented, stability problems are likely to occur during the experiment. This paper presents an approach for real-time hybrid simulation in which compensation for actuator dynamics is implemented using a model-based feedforward compensator.The method is used to evaluate the response of a semi-active control of a a an MR damper. Experimental results show good agreement with the predicted responses, demonstr ating the effectiveness of the method for structural control performance assessment.