The conductance of conductive ceramics, graphite and metal suspensions in aqueous KOH solutions was measured with the impedance technique using a four-electrode cell. The measurements were carried out for volume fractions up to high viscosities with particles of different sizes. A wide frequency range was used to investigate also the effect of particle-surface polarisation on the conductance. The results have been analysed in terms of the asymmetric and symmetric theories of Bruggeman and the GEM theory for a wide volume-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 polarisation resistivity is found due to shortcircuiting by direct particle-particle contact. The conductivities of the particles phase, calculated from measured values, are orders lower than predicted from conductivity 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.