Density data for dilute aqueous solutions of benzene and toluene are presented together with partial molar volumes at infinite dilution calculated from the experimental data. The measurements were performed at temperatures from (298.15 to 573.15) K and at pressures close to the saturated vapor pressure of water, at 30 MPa and at pressures between these limits. The data were obtained using a high-temperature high-pressure flow vibrating-tube densimeter. (C) 2003 Elsevier Ltd. All rights reserved.