Vapor-liquid equilibria of two compounds, glycerol (or 1,2,3-propanetriol) and 1,3-propanediol, and two mixtures, glycerol + water and glycerol + 1,3-propanediol, were determined using a static apparatus. The obtained pressure values range from 6 Pa to 45 kPa for the compounds and from (32 to 163) kPa for the mixtures. From the temperature dependence of the vapor pressures, the molar enthalpies of vaporization at the mean temperature of the experimental range were derived from the Clausius-Clapeyron equation. From these results the standard enthalpies of vaporization at T = 298.15 K were calculated. The experimental data of the mixtures were correlated using the nonrandom two-liquid (NRTL) model.