Excess volumes and viscosities at 303.15 K are reported for mixtures of 1,4-dioxane + 1,2-dichloroethane, + 1,1,1-trichloroethane, + 1,1,2,2-tetrachloroethane, + trichloroethene, and + tetrachloroethene. The results are interpreted in terms of molecular interactions between unlike molecules. Further, attempts are made to predict the viscosity values on the basis of the corresponding states approach and the Grunberg and Nissan treatment.