The cubic-plus-association (CPA) EoS is applied to multicomponent multiphase equilibria of systems containing MEG as a hydrate inhibitor. It is shown that the model provides very satisfactory prediction of the phase behavior for the systems tested. A more conventional engineering model for handling associating and polar molecules, an EoS/G(E) model is also tested, both for binary and multicomponent systems, and compared to the performance of the CPA EoS. It is found that the performance of CPA is overall superior while using fewer interaction parameters than the EoS/G(E) approach. (c) 2006 Elsevier B.V. All rights reserved.