The modification of the electrodynamic transport properties of conducting polypyrrole membranes by the use of dodecylsulfate anions during polymerization has been demonstrated. The use of small amounts of the surfactant counterion in combination with paratoluene sulfonate as the predominant anion during polymerization allows the production of conductive, mechanically stable materials with differing chemical properties. This, in turn, influences the transport characteristics and has been found to induce asymmetric transport character in the membrane.