The Extended UNIQUAC model for electrolyte systems, combined with the Soave-Redlich-Kwong equation of state is used to describe the complex vapor-liquid-solid equilibria of sulfur dioxide in electrolyte solutions. Model parameters based on 1500 experimental data points are presented. The parameters are applicable in the temperature range 0-110 degrees C, concentrations up to saturation and pressures up to 30 bar. This validity range corresponds to the experimental data used for the evaluation of parameters. (C) 2000 Elsevier Science Ltd. All rights reserved.