The effect of electrochemical promotion (NEMCA) was investigated for the oxidation of ethylene and propylene on Pt deposited on 4.5 mol% Y2O3-10 mol% TiO2-85.5 mol% ZrO2 (YZTi10) which is believed to be an ionic conductor with some n-type electronic conductivity in reducing environments. It was found that YZTi10 can induce the effect of electrochemical promotion for both C2H4 and C3H6 oxidation with apparent Faradaic efficiency, Lambda, values up to 10(3). The rate enhancement ratio, rho = r/r(o), however was found to be much smaller than in the cases where 8 mol% Y2O3-stabilized-ZrO2 (YSZ) or even TiO2 is used as the solid electrolyte and O2- donor. The origin of this difference is not clear.