The fusion reactor is still on the horizon for long-term energy generation. It is difficult to forecast the timescales for the development of the technology as a commercial power source. The UK Energy White Paper anticipates that nuclear fusion will be at an advanced stage of research and development by 2020 (Energy White Paper, 2003). Other commentators believe the reactor will still be in the development phase by 2030 (Energy Visions 2030 for Finland, 2003). Commercial realisation is unlikely to be before 2050 + . The fusion reactor is more attractive as a sustainable energy resource than the fission reactor since there are limitless fuel resources, there are no long-lived nuclides in the waste produced and the worst accident situations are of relatively low consequence.

Fusion research has and is being conducted in a number of collaborative international programmes. During the 1990s, the Joint European Torus (JET) project has made progress in generating significant amounts of energy. For the future generation of Tokamaks, interested nations will participate in the International Tokamak Experimental Reactor (ITER) project.