The model for self-association of ethanol in water which was established earlier by compressibility and infrared absorption measurements, has been further supported in the present work by monitoring fluorimetrically the variation of the solvatochromic Kamlet-Taft pi* parameter of ethanol-water mixtures over the entire mole fraction range. This model has been used to interpret the variation of the critical micellisation concentration (cmc) of sodium dodecyl sulphate in the presence of bovine serum albumin (BSA) in aqueous ethanol mixtures (as obtained from the tryptophan fluorescence intensity of BSA) in low ethanol mole fraction range.