Applicability of the extended real associated solution (ERAS) model to describe and predict properties of n-alcohol + unbranched monoether mixtures has been tested. Two versions of the model have been applied : its original, developed by Heintz [1] and a modified form, reported recently by Hofman and Casanova [2]. The basic assumption states that the purely physical contribution to the model should be meaningless. The model has three adjustable parameters which are common for all the mixtures considered. It has been applied to predict H-E, V-E and VLE data. The modified version gives acceptable results which for the non-volume properties are similar to those predicted by the Modified UNIFAC (Dortmund) using six parameters. The original ERAS model turned out to be inadequate.