Studies of the changes in ionic conductivity of anodic films following rapid changes of applied voltage or following a heat treatment of the film have shown that the activation energy and activation distance for ionic motion vary with changes in electric field and temperature. A consideration of these results along with other information obtained from the corrosion behavior of the films and from x‐ray diffraction by the films shows that a mechanism proposed earlier to account for ionic conduction in these films requires modification. It is suggested that a change of the applied field changes not only the number of conducting ions, as proposed earlier, but also changes the average local configuration in the glass‐like film and, hence, changes the mobility of the ions as well. Transient behavior similar to that shown by the films is also shown by anodic films of and , but not by anodic .