Research was conducted on the efficiency of cable and housing systems for body-powered, upper-limb prostheses. The tension required to actuate prosthetic components was found to grow exponentially with the product of the friction coefficient between the cable and housing and the total angle through which the cable bent. Values of the friction coefficients of various cable and housing material combinations were tabulated. The efficiency of the system can be calculated by knowing the cable did housing material and estimating the total angle of bend between the harness and prehensor. A sample calculation is provided.