Cationic and anionic polystyrene latices have been coated with uniform layers of zirconium compounds by ageing, at elevated temperatures, dispersions of the polymer colloid in the presence of aqueous solutions of zirconium sulphate, formamide, urea, and poly(vinylpyrrolidone). The thickness of the deposited layers could be altered by suitable adjustment of the reactant concentrations. It is suggested that the mechanism for the formation of the coating shell is based on heterocoagulation between the latex and in situ precipitated inorganic particles. Hollow colloidal spheres of zirconium compounds were obtained by calcination of the so-coated polystyrene latices at elevated temperatures in air.