This paper presents a systematic methodology for the design of a robust control system for processes described by an interval time-delay model. The design methodology is based on a two-degrees-of-freedom control configuration, for which a robust stabilizing controller and a prefilter are designed, respectively, to ensure robust stability and performance. In the design of the robust stabilizing controller, the system's interval time-delay process is approximated by means of a delay-free interval model so that the controller design method of Chen and Wang (1997) can be applied in a direct manner. Having characterized the robust stabilizing controller, a frequency technique (Chen and Wang, 2000) is utilized to ensure robust performance. An illustrative example is provided to demonstrate the design procedure as well as the effectiveness of the proposed scheme.