Crack-opening displacement (COD) measurements were performed on a commercial lead zirconate titanate (PZT). The intrinsic fracture toughness (or crack-tip toughness) of this material was determined using a new evaluation procedure, which takes into account the near-tip CON and complete crack profile CODs. The crack-tip toughness K-10 was determined from an extrapolation of COD data obtained at various loading stages, thus avoiding the complications caused by subcritical crack growth in PZT. Results for plane strain and plane stress condition are presented.