The effect of cobalt and tungsten addition to a Pd/Al2O3 catalyst on its catalytic activity, selectivity, and sulfur resistance during styrene selective hydrogenation at 353 K, 20 kg cm(-2) hydrogen pressure, and W/V = 0.002 g cm(-3) has been studied. Catalysts were characterized by XPS, XRD, TEM, and hydrogen and carbon monoxide chemisorption. An increase in activity and sulfur resistance was observed after both cobalt and tungsten addition, which is ascribed to the formation of very active Pd-Co and Pd-W interfaces. A decorative effect of cobalt and tungsten on palladium is suggested.