The mechanical behaviour of Al2O3 platelet-reinforced TiO2 bioceramics produced by hot-pressing has been investigated. The variation of the elastic constants, fracture strength and fracture toughness with the volume fraction of platelet content was studied. The addition of platelets did not affect the critical flaw size of the composites. This fact, and the good matrix/platelet interfacial bond resulted in a simultaneous increase of the fracture strength and toughness. The mechanical properties increased from K-lc = 2.4 MPa m(1/2) and sigma(0) = 215 MPa for pure TiO2 to K-lc = 3.3 MPa m(1/2) and sigma(0) = 265 MPa for a 30 vol% platelet-containing composite. The indentation technique demonstrated the anisotropic behaviour of the fracture toughness in the composites due to platelet orientation during hot-pressing. Load transfer was identified as the main reinforcing mechanism and the toughening effect could be assessed by a load transfer-based model equation. Fracture surface analysis showed mainly intercrystalline fracture for the TiO2 matrix, whilst with the composites, fracture became more transcrystalline with increasing platelet content.