The problem with the presence of several cathodic stripping peaks for HgSe in acidic Se(IV) solutions has been addressed using linear sweep, cyclic, square-wave and differential pulse stripping voltammetry at a hanging-mercury-drop electrode (HMDE). When very small amounts of selenium are accumulated, the selenium is dissolved in the HMDE and a single cathodic stripping peak is obtained. The solubility of selenium in mercury was estimated to 1-2 nmol cm(-3). The deposition of larger amounts of selenium gives rise to up to three film stripping peaks, most probably because of the reduction of thin two-dimensional and thicker three-dimensional HgSe islands formed simultaneously on the mercury surface. In the presence of Cl-, a single narrow HgSe film stripping peak is observed after deposition at a potential close to the positive potential limit of the electrode. The different voltammetric stripping techniques have been evaluated with respect to sensitivity and applicability. At low selenium concentrations, when the selenium is dissolved in the mercury electrode, square-wave or differential pulse stripping voltammetry is the method of choice. At higher concentrations, when most of the material is present as HgSe, linear sweep voltammetry is the most reliable technique.