We find that a Au(111) electrode is substantially roughened after a single monolayer of Pb is electro-plated and stripped from the surface in a linear sweep experiment. The roughened electrode surface rearranges into 20 to 150 Å diameter islands which are one atomic layer high, and separated by 20 to 50 Å. This process is observed on all samples, for sweep rates ranging from 0.5 to 1000 mV/s. If a partial layer of Pb is plated and then stripped, pitting and an increased overpotential for Pb deposition are observed only in the areas adjacent to the plated sites. We suggest that these observations are consistent with the formation of a PbAu alloy in the surface layer.