Reliable correlation and prediction of liquid densities are important for designing chemical processes at normal and elevated pressures. We have extended a corresponding states model from molecular theory to yield a robust method for quality testing of experimental data that also provides predicted values at unmeasured conditions. The model has been shown to successfully validate and represent the pressure and temperature dependence of liquid densities greater than 1.5 of the critical density for pure compounds, binary mixtures, and ternary mixtures from the triple to critical temperatures at pressures up to 1000 MPa. The systems include the full range of organic compounds, including complex mixtures, and ionic liquids. Minimal data are required for making predictions.The presentation will show the implementation of the method, criteria for its deployment, examples of its application to a wide variety of systems over great ranges of conditions, and considerations of further developments.