The design and analysis of a robust proportional, integral, derivative (PID) controller for a hydraulic turbine generator governor using a frequency-response technique is presented. The approach uses data from literature on the turbine and on the interconnected system in various modes of operation through a model in the literature to design a single PID controller to guarantee stability and performance over the entire operating range. To ensure stability of the loop for as yet unanticipated operating situations, gain margin, and phase margin, constraints are imposed during the design of the controller. The new PID governor is compared with a high-order controller designed by the H-infinity method.