When copper or lead-activated sphalerite is mounted in carbon paste, an electrode is obtained which is suitable for use in dynamic electrochemical measurements. Voltammograms of copper-activated sphalerite in carbon paste show well-defined anodic and cathodic waves which respond in a complex manner to changes in experimental conditions. When the electrodes are contacted with solutions containing ethyl xanthate, two oxidation waves are observed. The first of these is a highly irreversible surface-area-limited adsorption process, and the second is a transport-controlled reaction. This work confirms the general belief that the flotation chemistry of sphalerite is essentially electrochemical in nature, and provides a tool which can be used to study the activation process as well as the reactions of collectors and other reagents with activated sphalerite, and perhaps in the control of the flotation process.