Accurate diffusion coefficient data are reported for highly nonideal binary mixtures. The mixtures consist of an alcohol (ethanol, 1-propanol, 1-butanol) dissolved in hexane, cyclohexane, carbon tetrachloride, or toluene. All measurements have been conducted over the whole concentration range at various temperatures, (25, 30, and 35) degrees C, by means of the Taylor dispersion technique. The uncertainty of the reported data is estimated to be within 3.10(-11) m(2.)s(-1).