We report measurements on the modification of the work function (WF) of indium-tin-oxide (ITO) by deposition of Au and Pt overlayers, chosen because of their high WF and inertness. ITO films on glass substrates (resistance similar to 10 Omega/sq) were cleaned with an ultraviolet (UV)-ozone treatment before entry into an ultrahigh vacuum system. Auger electron spectroscopy was used to determine the surface composition. The change of WF of the surface (+/- 10 mV) was determined by a Kelvin probe technique and correlated with the absolute coverage (in the range 0 5 x 10(15) AU cm(-2). The final WF values were not very different from the non-UV-ozone treated samples. Studies on bulk Au and ITO covered by Au in a single deposition, showed that the low final WF value in the sequential experiments was attributable to adsorption of hydrocarbons from the 1 x 10(-10) Torr vacuum, and that useful increases in WF art attainable on ITO electrodes with gold layers which are thin enough to cause no obvious change in ITO's transparency (less than or equal to 10%). A similar trend was observed for the Pt layer but with less sensitivity to hydrocarbon adsorption.