The water-gas shift (WGS) activity of bimetallic Pt-Ni/Al2O3 catalysts was investigated in the temperature range 200-450 degrees C using an idealized feed composition consisting of 3% CO and 6%-10% H2O. The effects of the Ni content, space velocity, and H2O/CO ratio on the catalytic performance of the catalysts were studied. An increase in the Ni content and H2O/CO ratio shifted the carbon monoxide conversion-temperature curve toward lower reaction temperatures. No detectable methane formation was observed in the catalytic reaction tests. The results indicate that Pt-Ni/Al2O3 catalysts are highly selective and active for water-gas shift reactions under idealized conditions.