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A novel approach is presented to the problem of robust control strategy for an Exhaust Gas Recirculation (EGR) system. Modeling issues and controller design for an electric valve are presented. Robustness is one of the main issues due to nonlinearities (hysteresis, friction), computational time delays, and the effects of complex exhaust gas dynamics. A high level of noise, due to engine vibrations, makes the input-output model identification very difficult. We use a special windowing technique to successfully complete the identification. It was found that a good approximation of the system dynamics consists of a first order transfer function with a time delay whose parameters depend on the operating conditions (engine load, r.p.m.). Thus, the nonlinear effects of friction and hysteresis are replaced, for the purpose of control design, by variable gain, time delay, and time constant of the linear model.