In the past, the extended corresponding states approach to fluid property prediction has been restricted to non-polar fluids (e.g., hydrocarbons and some common non-polar inorganics) due to the lack of an accurate way to predict the required shape factors. In this work, a new predictive method to obtain shape factors for the extended corresponding states theory (ECST) has been developed which is applicable to both polar and non-polar fluids. The details of this revised extended corresponding states model are presented. The resulting model has been applied with success to a wide variety of pure fluids including alcohols, amines, ethers and substituted aromatics. Detailed extended corresponding states shape factor results are presented here for hydrocarbons, alkenes, non-polar inorganics, polar inorganics and refrigerants. (C) 1998 Elsevier Science B.V. All rights reserved.