The polymer electrolyte membrane fuel cell (PEMFC) has been projected to be the fuel cell of choice for future automotive applications. Among the most challenging aspects of the this application is the occurrence of severe and frequent changes in power demand. However, set-point tracking in a PEMFC is complicated by the need to regulate many additional operating variables. In this work, a simplistic PEMFC model is used to illustrate the operational goals and challenges associated with power set-point tracking. Among the measures of performance, we find tracking response time, available power range, and energy conversion efficiency. Challenges range from stack cooling and oxygen starvation to membrane flooding and dehydration. In this work, a feedback structure is proposed to address these many facets of the PEMFC control problem.