The submicron Ce-ZrO2 (13 mol% CeO2) powder was found to be slightly soluble at acidic conditions and the isoelectric point was determined to pHiep= 7.9 using electroacoustics in concentrated suspensions. The adsorption isotherms of two well characterised polyelectrolyte dispersants, Dispex A40 and Duramax D3007, could be related to the molecular structure. A combination of electroacoustic and rheological measurements showed that the viscosity is at a minimum at monolayer coverage of the dispersant when the covered particles are highly charged. The study illustrates how rheology and electroacoustics can be utilised in the investigation and optimisation of the properties of concentrated ceramic suspensions.