Hydrotropic substances, such as, sodium P-toluene sulfonate, potassium P -toluene sulfonate, sodium P -xylene sulfonate, potassium P-xylene sulfonate, sodium benzoate, potassium benzoate, etc., in aqueous solutions, at relatively high concentrations, have been used successfully to separate mixtures of close boiling point substances like 2,6-xylenol/P-cresol, pheno1/o-chlorophenol, P -chlorophenol/2,4-dichlorophenol, and o-cresol76-chloro-o-cresol, dissolved in a suitable solvent. Very high values of separation factor in the range of 10 to 66 have been realised and this novel method appears to be promising for industrial utilization.