The complex interactions of polyethylene glycols and their derivatives with a wide variety of inorganic and organic chemical were discussed. Subtleties of this association reaction with polyvalent cation salts, phenols, carboxylic acids, urea and the halogens wee revealed through experimental observation of changes in solubility, degree of dispersion or flocculation and the potency of preservatives and pharmaceutical. The broad significance of such interactions was verified by generous literature support in many unrelated areas of technology. Through a better understanding of the equilibria and the competitive reactions involved in complex mixtures novel and utilitarian application will continue to be found for the association complexes of these polyether derivatives.