New results in the electrocatalysis of organic reactions based in the use of spectroscopic methods are presented. The methods and systems discussed are : (a) thermal desorption spectroscopy applied to the characterization of the metal-CO bond on Pt and Pt-Ru alloys; (b) in situ Fourier transform infrared spectroscopy (FTIRS) and differential electrochemical mass spectrometry (DEMS) used to establish the composition of adsorbed ethanol at platinum; and (c) DEMS applied to discriminte between bulk and adsorbate reactions during the oxidation of formic acid catalysed by adsorbed Pb at platinum. The possibility of a reaction pathway highlighting the role of water is suggested.