Molar enthalpies of vaporization Delta(l)(g)H(m)(o) of seven benzyl halides and seven benzyl ethers have been obtained from the temperature dependence of the vapor pressure measured by the transpiration method. These values and the correlation-gas chromatography method, based on Kovat's index, have been applied for the determination of Delta(l)(9)H(m)(o) of three cumyl halides (Cl, Br, and I). The data obtained for Delta(1)(g)H(m)(o) of benzyl derivatives have been checked successfully for internal consistency using enthalpies of formation of alkyl halides and alkyl ethers available from the literature.