Power generation systems based on solid oxide fuels cells (SOFCS), which operate at temperatures between 700 and 1000 C, are being developed for use with hydrocarbon fuels, such as natural gas, propane, and diesel, which typically contain trace amounts of sulfur. The presence of trace impurities, such as residual hydrocarbons and sulfur-containing species (e.g., H2S), can lead to degradation of nickel-based reforming catalysts and nickel-based anodes that currently are used in most SOFC system designs. Thus, sulfur removal systems currently are used, either before or after reforming. For these systems, on-line sensing of sulfur contents in the reformed fuel is desired, both to monitor the efficiency of the sulfur-removal systems and to protect the fuel cell from irreversible degradation. NexTech Materials has identified a number of ceramic-based sensing strategies for detection of low levels of sulfur (up to 10 ppm H2S), and this presentation will describe the status of this development effort.