Much effort has recently been put on the study of measurement technique and prediction for the vapor-liquid equilibrium at high pressure because of their increasing importance in the enhanced oil recovery （EOR） by CO₂ gas, liquefaction of solid fuels, and extraction of less volatile substance with supercritical gases.
This review presents the recent trend of vapor-liquid equilibrium studies at high pressure, discussion on the difficulties associated with these studies, and a survey of progress in the development of new or modified equation of state and prediction methods applicable to phase equilibria of EOR and supercritical gas extraction.