Process for producing multicoat color and/or effect paint systems comprising a color and/or effect basecoat (A) and a transparent topcoat (B) by a wet-on-wet method using a color and/or effect coating material (A) and a transparent coating material (B), the coating material (A) being prepared by separately preparing an aqueous, structurally viscous powder dispersion (A1), in an amount, based on (A), of 50% to 100% by weight, mixing it with the other constituents (A2) of the coating material (A), and homogenizing the resulting mixtures (A).