A program designed to control a hydraulic motor using either PI or hybrid fuzzy logic - PI control was written. The motor under control was part of a hydrostatic transmission. The real time closed loop control software was written to run on an IBM PC AT or equivalent. Additional software was written to generate the fuzzy rule set to be used with the hybrid fuzzy-PI controller. Test results indicate that hybrid fuzzy logic - PI control of the motor speed was more effective than pure PI control for set point changes. Load changes were not tested.