The adsorption of CO and CO2 on Pt supported on ZrO2 and Ce/La-promoted ZrO2 was studied using DRIFTS. The presence of both La and Ce resulted in a decrease in the adsorption of CO at room temperature after reduction at 350 degrees C. The reduction in the CO adsorption is ascribed to an increase in the support reducibility when La and Ce are both present. Reduction at 350 degrees C leads to the formation of oxygen defects in the dual promoted support which have been probed using DRIFTS to monitor CO2 dissociation. Hydrogen assisted dissociation is demonstrated on the ZrO2, CeZrO2, and LaZrO2 supports. In the absence of hydrogen, the presence of oxygen vacancies is shown to be necessary for CO2 dissociation.