Abstract: A dynamic, compact, lightweight fuel processor that is capable of converting carbonaceous fuels to hydrogen rich gases suitable for all types of fuel cells or chemical processing applications. The fuel processor and process are based on the autothermal hydrodesulfurizing reforming reaction, followed by clean up of byproduct sulfur-containing gases and carbon monoxide that poison the fuel cell electrocatalyst. The fuel processor uses proprietary catalysts and hardware designs that enable the conversion in an energy efficient manner while maintaining desirable performance characteristics such as rapid start-stop and fast response to load change capabilities.