Proton exchange membrane (PEM) fuel cells suffer noticeable power loss when operated at high power output. This paper proposes a hybridization scheme for a PEM fuel cell/supercapacitor system operating in three different regimes: “Flat,” “Uphill,” and “Downhill.” Transitions among operational regimes are governed by logical statements, which compare operational parameters against threshold values. These threshold values were obtained using a genetic optimization (GO) algorithm. The hybridization problem is analyzed in a simulation environment before the solution is implemented in an actual laboratory prototype. Results and discussion are presented to demonstrate the soundness of the proposed solution. The approach presented in this paper is suitable for applications where sudden changes in power demand occur.