The catalytic reaction of the melt transesterification of diphenyl carbonate (DPC) and bisphenol-A (BPA) is investigated theoretically. A reaction mechanism based on the nucleophilic substitution on the carbonyl group of reactants is proposed for the description of the kinetic behavior of the reaction under consideration. Previous models are extended so that the kinetic model derived is not only more physically sound, but also involves a less number of adjustable parameters. The applicability of the present model is justified by fitting it to the available experimental data reported in the literature, and its performance is found to be satisfactory for a wide range of operating conditions. We conclude that melt transesterification of DPC and BPA is of reversible nature; the forward reaction is second order in the concentrations of DPC and catalyst, and the reverse reaction is third order in the concentrations of phenol, oligomer, and catalyst. (C) 2003 Elsevier Ltd. All rights reserved.