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Transparent polycrystalline Nd:YAG ceramics were fabricated by solid-state reactive sintering a mixture of commercial Al 2 O 3 , Y 2 O 3 , and Nd 2 O 3 powders. The powders were mixed in methanol and doped with 0.5 wt% tetraethoxysilane (TEOS), dried, and pressed. Pressed samples were sintered from 17001 to 18501C in vacuum without calcination. Transparent fully dense samples with average grain sizes of B50 lm were obtained at 18001C for all Nd 2 O 3 levels studied (0, 1, 3, and 5 at.%). The sintering temperature was little affected by Nd concentration, but SiO 2 doping lowered the sintering temperature by B1001C. Abnormal grain growth was frequently observed in samples sintered at 18501C. The Nd concentration was determined by energy-dispersive spectroscopy to be uniform throughout the samples. The in-line transmittance was 480% in the 350-900 nm range regardless of the Nd concentration. The best 1 at.% Nd:YAG ceramics (2 mm thick) achieved 84% transmittance, which is equivalent to 0.9 at.% Nd:YAG single crystals grown by the Czochralski method. 1945J ournal