Dissolution enthalpies of L-alpha-alanine, L-alpha-valine and L-alpha-leucine in aqueous ethanol solutions have been measured by calorimetry at 298.15 K. The results obtained were used to calculate the enthalpic heterogeneous pair interaction coefficients between zwitterions of amino acids and a molecule of ethanol in water. (C) 2005 Elsevier B.V. All rights reserved.