Powders of nanocrystalline zirconia doped with 3-30 mol% alumina have been synthesized using chemical vapor synthesis (CVS), Dense or mesoporous ceramics of small and narrowly distributed grain and pore sizes in the nanometer range are obtained via pressureless vacuum sintering. The microstructural development of the doped samples is strongly dependent on the alumina content, Sintering of zirconia samples with 3 and 5 mol% alumina at temperatures of 1000 degrees C for 1 h results in fully dense, transparent ceramics with grain sizes of 40-45 nm and homogeneous microstructures.