The electrochemical behavior of silver (100) and (111) single crystal surfaces was examined by cyclic voltammetry in aqueous NaOH solution. In the 'double layer' region (between -1.2 and 0.1 V (SCE)) adsorption of OH - ions followed by phase transformation into an Ag-OH monolayer was found to take place. The difference in peak potentials recorded in 0.1 and 0.01 mol dm - 3 NaOH solutions of about 60 mV indicates that one electron is exchanged in the overall electrochemical reaction, implying a complete charge transfer between OH - ions and the silver surface. The adsorption process has been modeled to a Frumkin adsorption isotherm. Further oxidation of silver into Ag 2 O takes place at more positive potentials. The formation of bulk Ag 2 O results in considerable change to the original single crystal surface. This is likely to be due to roughening of the silver surface as a consequence of the formation and reduction of the oxide.