Viscosities and excess viscosities for three binary systems (2-propanol + benzyl alcohol, 2-propanol + 2phenylethanol, and benzyl alcohol + 2-phenylethanol) were computed at T= (298.15, 308.15, and 318.15) K over the concentration range 0.05-0.95 at atmospheric pressure and compared with the experimental work of Ching-Ta et al. Different theoretical models assuming association and non-association of the components of the mixtures, were used to predict the behavior of the studied liquids, which would typically show strong interactions. The properties were fitted to the Redlich-Kister polynomial equation to estimate the binary coefficients and standard errors. The excess viscosities were used to study the nature and extent of the molecular interactions in the binary mixtures. McAllister multi body interaction model was used to correlate the properties of the binary liquid mixtures. Testing of the models for the different systems showed that, compared with the non-association model theoretical results, the association model theoretical results were more consistent with the experimental results.