Important parameters such as ion exchange capacity, conductivity, permselectivity, quantity of sorbed electrolyte and water uptake of the Selemion AMV anion exchange membrane conditioned in KCl and NaCl solutions were determined in order to assess the applicability of the two-phase model of structure microheterogeneity to this case. In general, a good consistency between the experimental results and the theoretical approach was obtained. Electrical conductivity measurements allowed evaluating the volume fractions of two distinct internal phases inside the membrane. Aside from the chronopotentiometric behaviour of the AMV membrane, SEM and XPS techniques contributed to provide a better description of the overall membrane homogeneity. Influence of co-ions in relation with water uptakes on the conductivity and permselectivity of the studied membrane has been shown. An existence of partition equilibrium between the electrolytes sorbed in the membrane and the external solution confirmed in this work should be introduced within the microheterogeneous model. (C) 2009 Elsevier B.V. All rights reserved