The conductance of conductive ceramics, graphite and metal suspensions in aq. KOH solns. was measured with the impedance technique using a 4-electrode cell. The measurements were carried out for vol. fractions up to high viscosities with particles of different sizes. A wide frequency range was used to study the effect of particle-surface polarization on the conductance. The results were analyzed in terms of the asym. and sym. theories of Bruggeman and the GEM theory for a wide vol.-fraction range of suspended particles. Depending on the suspended material, particle size and electrolyte properties, the suspensions reveal flocculation or chain formation. In case of chain formation, sometimes a decrease of the polarization resistivity is found due to short-circuiting by direct particle-particle contact. The conductivities of the particles phase, calcd. from measured values, are orders lower than predicted from cond. data of the pure materials. This is attributed to the occurrence of a constriction resistance and film resistance between the particles in the case of flocculation or chain formation as well as to poor wetting of the particles. [on SciFinder (R)]