The Joint European Torus (JET) is the largest project in the coordinated programme of EURATOM, whose fusion programme is designed to lead ultimately to the construction of safe, environmentally sound prototype reactors. JET experiments started in 1983 and towards the end of 1991, the performance of JET plasmas had improved sufficiently to warrant the first tokamak experiments using a deuterium-tritium (D-T) fuel mixture. Since then, the interior of the JET vacuum vessel has been reconstructed and operation has just restarted in the new pumped divertor configuration. The programme is presently approved to the end of 1996, and a further extension to the end of 1999 is being proposed to confront the most critical scientific issues that must be solved before the International Thermonuclear Experimental Reactor (ITER) can be constructed.