The effect on neutral beam design and reactor performance of using high-energy (∼3- to 10-MeV) tritium neutral beams to drive steady-state tokamak reactors is considered. The lower current of such beams leads to several advantages over relatively lower energy 2-MeV deuterium neutral beams. The major disadvantage is the reduction of the reactor output caused by raising the beam energy above the optimal energy for current drive (3 to 5 MeV) and thus lowering the current-drive efficiency.