An alumina-based ceramic codispersed with zirconia and mullite was synthesized with a submicron grain size. At high temperatures, steady-state creep with very limited grain growth was achieved for samples with 40 vol% alumina, 30 vol% zirconia, and 30 vol% mullite (AZ30M30). Constant stress compressive creep behavior of AZ30M30 showed a stress exponent of 2 and an activation energy of 880 kJ/mol. A strain rate of 0.01 s(-1) was obtained for AZ30M30 at 60 MPa and 1500 degrees C, indicating the potential for high-strain-rate superplasticity.