Nanocrystalline electrochromic electrodes offer a promising outlook for the realization of displays characterized by sharp contrast and fast switching. These electrodes are constituted of sintered nanoparticles of a semiconductor, for instance titanium dioxide. Owing to the high porosity of the material, the signal produced by the color change associated to the oxidation or reduction of an adsorbed molecular monolayer can be amplified by a factor of 100–1000, allowing transmittance changes from 79 to 11% of the complete electrode in less than 1 s.