Highly sinterable yttria-doped ceria powder (YO1.5)x (CeO2)1 − x (x = 0.1–0.33) was fabricated by an optimized coprecipitation route. Compacted bodies could be sintered to impermeability at 1200 °C and near full density at 1300 °C, among the lowest temperatures reported for doped ceria densification. Ceria diffusion is important above 1400 °C. Excellent conduction properties were observed: high ionic conductivity (6.5 S m−1 at 750 °C for Ce0.8Y0.2O1.9), low activation energy (0.7 eV) and vanishing grain-boundary resistance