The paper describes the application of the theoretically-based scheme of Vesovic-Wakeham, modified by making use of the hard-sphere model of Dymond-Assael, to the prediction of the viscosity and thermal conductivity of liquid mixtures. The purpose of the paper is to examine this scheme in more detail than earlier in order to find out under what circumstances it works well and when it fails. Hence, the scheme is employed to predict for the first time, the viscosity and thermal conductivity of a wide range of mixtures of quite disparate liquids from groups of hydrocarbons, through combinations of alcohols and hydrocarbons, to halogenated refrigerants. It will be shown that, in all cases, provided that the mass ratio of the pure components is close to unity, the predictions show excellent agreement with experiment.