An improved theoretical analysis is presented for the strength and mechanical reliability of ceramic materials with an R-curve characteristic. There is good agreement between the predicted flexural strength distribution of an Al2O3/ZrO2 ceramic and experimental data. Unlike the conventional two-pa ra meter Weibull approach, this new ana lysis is able to predict the non-linearity observed in the InIn 1/(1-P-f) versus In sigma(f) strength distribution curve. Compared to the untoughened Griffith material, the R-curve material has higher strength and better strength reliability.