The reaction of S-2 with Pt-Al alloys has been investigated using core- and valence-level photoemission. The Pt-Al alloys display a Pt 5d band that appears at much higher binding energy (1.8-2.1 eV) than in metallic Pt. This is accompanied by positive shifts in the Pt 4f (0.3-1.3 eV) and Al 2s (0.1-0.3 eV) core levels. The electronic perturbations in Pt do not increase the reactivity of this metal toward sulfur. After exposing Pt-Al alloys to S-2 gas, aluminum is extensively sulfided, while platinum remains in a metallic state. The Pt<->AlSx interactions are much weaker than Pt<->Al interactions. The chemisorption of S-2 induces the segregation of aluminum toward the surface of the alloys. The behavior observed for the PtAlx surfaces in the presence of sulfur is different from that seen for Cu/Pt (111) and Ag/Pt (111) surfaces, where the admetals promote Pt<->S interactions and the formation of several layers of platinum sulfide. Changes in the nature of the bimetallic bond and in the relative stability of the metal sulfides are responsible for this difference in behavior.