The limitations of ac techniques used to study the high temperature transport properties of mixed conductors obtained by addition of a mixed valence dopant to zirconia based oxygen ion conductors suggested the use of alternative dc techniques. In this paper an attempt is made to predict the behavior of two different types of mixed conductors if characterized in terms of ionic transference numbers by open circuit electromotive force (EMF) measurements, electrochemical permeability or by using the ion blocking electrode technique. The relevant relations required for the interpretation of experimental data were revised, and the advantages of each dc technique were discussed.