Vapour pressures of tetrachloromethane + 1, 1,2,2-tetrachloroethane (or +tetrachloroethene) at nine temperatures between 283.15 and 323.15 K were measured by a static method. The reduction of the vapour pressures to obtain activity coefficients and excess molar Gibbs energies was carried out by fitting the vapour pressure data to the Redlich-Kister polynomial according to Barker's method. A comparative analysis about the thermodynamic behaviour of both systems is performed, taking into account the resonance effect in tetrachloroethene and self-association in 1, 1,2,2-tetrachloroethane. For the 1, 1,2,2-tetrachloroethane + tetrachloromethane system we have fitted dispersive interchange coefficients for the DISQUAC-model, observing that reproduces satisfactorily the G(E)-experimental values at all temperatures. (C) 2004 Elsevier B.V. All rights reserved.