Duplex (two‐phase) microstructures and laminar composites offer some unique opportunities for improving the room‐temperature mechanical reliability (e.g., flaw tolerance) and the high‐temperature microstructural stability (e.g., resistance to grain growth and creep damage) of structural ceramic materials. Examples illustrating the approach to designing novel multiphase microstructures and laminar composites with enhanced structural reliability are given. These are based on current work on various alumina‐based ceramics as well as zirconia‐, silicon nitride‐, and silicon carbide‐containing ceramics. Critical issues and areas for future work