A new simple equation for the vapour-pressure of pure substances is proposed. It is a three-constant non linear correlation that reproduces with high accuracy the vapor-liquid equilibrium data, even at low reduced temperatures. Applied to 34 fluids with acentric factors varying in the range between -0.4 and +0.4, the model is shown to be very performant. The average relative deviation between thee data and the estimated values is in the order of 0.16%, with a maximum at 0.3%. Based on this model an accurate three-parameter generalized vapor pressure correlation which needs P-c, T-c and omega as inputs is established. (c) 2005 Elsevier B.V. All rights reserved.