The saturation pressures of propylene glycol at (393 to 423) K, 2-(2-hexyloxyetoxy)ethanol at (402 to 423) K, 1-methyl-2-pyrrolidone at (352 to 378) K, and 1-methoxypropan-2-ol at (347 to 378) K were measured by an ebulliometric method. The vapor-liquid equilibrium (P, T, x, y) was measured by an ebulliometric method for the system propylene glycol + 2-(2-hexyloxyethoxy)ethanol at (403.15, 413.15, and 423.15) K and for the system 1-methyl-2-pyrrolidone + 1-methoxypropan-2-ol at (353.15, 363.15, and 373.15) K. The experimental vapor pressures were correlated with Antoine and association + equation of state (AEOS) equations, while the VLE was correlated with the AEOS equation of state for all the temperature intervals and with equations representing activity coefficients at specific particular isotherms.