The behaviour of cyanide on platinum electrodes at anodic potentials has been studied by voltammetric and Fourier transform infrared reflectance spectroscopic techniques. The voltammetry shows that cyanide adsorbs on platinum at potentials more negative than –0.8 V (SCE). Potential-sensitive infrared absorptions appearing between 2200 and 2250 cm^–1 are tentatively assigned to strongly adsorbed cyanide species. Another band at 2074.5 cm^–1 shows no change in wavenumber with potential and is thought to be associated with cyanide in the double-layer region. An absorption at 2169 cm^–1, which appears with significant intensity at anodic potentials, has been attributed to bulk cyanate. Other features at 2093 and 2343 cm^–1 are assigned to aqueous hydrogen cyanide and carbon dioxide, respectively, possibly formed as a result of changes in interfacial pH associated with electro-oxidation.