Iodine is taken up by polyvinyl alcohol from aqueous solution according to the adsorption isotherm. From aqueous methyl and ethyl alcohol solutions, the sorption obeys Henry's law. One electrolyte measured was absorbed by the colloid. The relation of Kroeker between weight of adsorbent and sorption of adsorbate, keeping total adsorbate constant, holds only at higher concentrations of adsorbent. Pre-absorption of an electrolyte does not materially affect adsorption of iodine by polyvinyl alcohol. The nature of the blue polyvinyl alcohol-iodine complex is discussed.