ABSTRACT CTS-9714979 John O'Connell Thermodynamic properties are a principal basis for innovative and improved chemical process synthesis, design and optimization. With the advent of high-speed computers, many of the trial and error steps of bench scale and pilot plant development can be eliminated if reliable and accurate methods are available for 1) volumes to size units, 2) energies to obtain heat and work effects, and 3) chemical potentials/fugacities to calculate phase and reaction equilibria for separation and reaction limits. Since thermodynamics show how all of these properties can be obtained from rigorous mathematical operations on models such as the equation of state, when accurate expressions have been derived and parameter values fitted to the data. Large amounts of quantitative results can be directly obtained. Thus, the goal of considerable current research is to find models that can describe many classes of substances, mixtures and conditions. The Project for Standardized Validation of Physical Properties Models (SVPPM) has been initiated to provide basic information to model generators and users about the consistency, behavior, accuracy, and reliability for quantitative property descriptions of chemical systems. Interactions with various industrial experts have stimulated enthusiasm and guidance for the project; financial support has been provided from NIST. An organizational structure has been proposed and will be implemented in stages. Current goals are 1) to establish a computer program for a range of tests on equations of that will be accessible via the internet and 2) to demonstrate it at the 8th International Conference on Properties and Phase Equilibria for Product and Process Design in April, 1998. ***