Vapour pressures and the molar enthalpies of vapourization of the gamma-lactones (gamma-valerolactone, gamma-hexanolactone, gamma-heptanolactone, gamma-nonanolactone, and gamma-decanolactone) have been determined by the transpiration method. These results together with a large number of experimental data from the literature have been checked for internal consistency. This collection has been used for development of group-additivity procedure for prediction of vapourization enthalpies of lactones. (C) 2008 Elsevier Ltd. All rights reserved.