Two hydrophobic ABA three block thermoplastic elastomers, namely styrene/butadiene/styrene (SBS) and styrene/ethylene-butylene/styrene (SEBS), have been employed to prepare membranes by their casting from toluene solutions. While they were expected to be permselective to alcohols from water-alcohol mixtures, they did not display the expected permselectivity. Their modification, by the inclusion of divinylbenzene (DVB) into the casting solutions followed by polymerization, generated increased alcohol permselectivity and permeation rate. There exists an optimum proportion of DVB for which the separation factor and the permeation rate became maximal. The permeation rate became higher with increasing operating temperature, whereas the separation factor decreased moderately. As expected, the pervaporation performance for alcohols from water-alcohol mixtures increases with an increase in the hydrophobicity of the alcohol.