The saturation pressures of acetonitrile (302 to 353) K, propanenitrile (309 to 353) K, 1-pentanamine (322 to 378) K, and 1-methoxy-2-propanol (331 to 373) K were measured by an ebulliometric method. The vapor-liquid equilibrium (p, T, x, y) was measured by an ebulliometric method for the systems acetonitrile + propanenitrile at (313.15, 323.15, and 343.15) K and 1-pentanamine + 1-methoxy-2-propanol at (333.15, 343.15, and 353.15) K. The experimental vapor pressures were correlated with the Antoine equation and, for pentanamine + 1-methoxy-2-propanol, also with the AEOS equation of state. The VLE data were correlated with the "y/phi" method. For the system 1-pentanamine + 1-methoxy-2-propanol the prediction with the AEOS model has been proposed. In this system an almost tangent negative azeotrope is observed for temperatures below 350 K.