The effect of post-irradiation annealing at 300 T for 50 h on the microstructure and mechanical properties of CuCrZr irradiated to 0.2 and 0.3 dpa at 100 degreesC has been evaluated. The post-irradiation annealing removes the yield point phenomenon, lowers the strength and improves the ductility and work hardening of the material. It does not, however, completely remove the effects of irradiation as the annealed material is still considerably stronger and less ductile than the unirradiated CuCrZr alloy. The removal of the yield point phenomenon is attributed to a decrease in raft formation and dislocation decoration, weakening the dislocation pinning and allowing more homogeneous generation of dislocations within the material. The segregation of solute additions, impurities and transmutation elements as well as precipitation at dislocation segments and loops needs to be further investigated to fully understand the mechanical properties. (C) 2002 Elsevier Science B.V. All rights reserved.