The Joint European Torus (JET) machine has for a number of years been looking at the experimental feasibility of producing fusion energy from isotopes of hydrogen within a magnetically confined vessel called a tokamak. The machine produces plasmas at temperatures of up to 100 million degrees Centigrade in pulses of 10s duration. Conclusions from this project will provide the building blocks for the next machine, which may be the prototype fusionreactor called ITER.