The H2/O2 reaction on a polycrystalline palladium foil has been studied. The experimental methods used were Laser-Induced Fluorescence (LIF) and microcalorimetry. The reaction was also simulated with the Chemkin software package. The water production maximum occurs at 40% H2 and the OH desorption has its maximum at 10% H2, at a total pressure of 100 mTorr (13 Pa) and a catalyst temperature of 1300 K. It is concluded, in agreement with the simulations, that the main water-forming reaction at these experimental conditions is OH+H→H2O. From the water production maximum the quotient of the initial sticking coefficient for hydrogen and oxygen (SH2(0)/SO2(0)) is calculated to be 0.75(±0.1).