This paper describes the application of Taguchi methods [1,2,3] to the parameter sizing stage of fluid power system design. Taguchi methods have become almost synonymous with robust design and are used to design systems that are tolerant to the effects of noise factors. Noise factors are defined as anything that causes changes in the functional characteristics or performance of the system that are not controllable. In the hydraulic circuit example used in this paper, these noise factors are assumed to be effects of component failure. The method is therefore being used to select design parameter values such that the resulting circuits exhibit some tolerance to the initial development of faults in the system which will allow the system to continue to operate for a short period of time without catastrophic failure occurring.