The alloy V-15Cr-5Ti was cyclotron-implanted with 80 appm He and subsequently irradiated in the Experimental Breeder Reactor (EBR-II) to 30 displacements per atom (dpa). The same alloy was also irradiated in the 10, 20, and 30% cold-worked conditions. Irradiation temperatures ranged from 400 to 700°C. No significant effects of helium on mechanical properties were found in this temperature range although the neutron irradiation shifted the temperature of transition from cleavage to ductile fracture to about 625°C. Ten percent cold work was found to have a beneficial effect in reducing the tendency for cleavage fracture following irradiation, but high levels (20%) were observed to reduce ductility. Still higher levels (30%) improved ductility by inducing recovery during the elevated-temperature irradiation. Swelling was found to be negligible, but precipitates—titanium oxides or carbonitrides—contained substantial cavities.