This paper summarizes our development of solid oxide fuel cells (SOFCs) using hydrocarbon fuels. Minimization of particle agglomeration during the coating and drying steps has reduced the sintering temperatures to obtain dense yttria-stabilized zirconia (YSZ) electrolytes to as low as 1200 degreesC. The development of Cu/CeO2/YSZ anode composites in SOFCs for the direct electrochemical oxidation of dry hydrocarbon fuels is described, These anode-supported cells are fabricated by a double-tape casting technique. and impregnation of aqueous solutions of Cu(NO3)(2) and Ce(NO3)(2) into a porous YSZ anode structure. Single cells with these Cu/CeO2/YSZ anode composites have operated in both dry gaseous (methane, butane) and liquid (synthetic diesel) hydrocarbon fuel environments at intermediate temperatures.