The theoretical models that might be used to forecast the electrical behaviour of ionic conductor composites for application in SOFCs are reviewed. A comparison of the different models is performed and comparative analysis of their power is presented on the basis of a case simulation (YSZ (7,54 mol%Y2O3)-Al2O3 (5 wt%) composite). The lack of systematic experimental works makes a wide comparison with the theoretical results very difficult, so the real power of the models can not yet be fully assessed and only introductory considerations are tentatively given. Nevertheless from the preliminary results, it seems possible to affirm that Electrical Network Models are able to better sustain the simulation of the electrical properties of YSZ-Al2O3 composites. Certainly many other improvements have to be done before ENMs became confident tools for tailoring "ab initio" the electrical properties of two phase mixtures.