The contribution of the methylene group to the distribution coefficient (Δ logKD/CH2) has been obtained for 38 different solvents. For nonpolar solvents Δ logKD/CH2is in the range 0.60 to 0.64, whereas for polar solvents it is in the range 0.33 to 0.58. Attempts have been made to correlate group values with solvent polarity, and it is found that the solubility of water in the organic solvent phase has a profound effect. Equations are derived from the three-suffix Margules equation for a ternary system that relate Δ logKD/CH2to mole fraction solubility of water. The agreement between theoretical and experimental values is good for the case of alcohol solvents. Correlations with the empirical solvent polarity parameter of Reichardt are also examined.