The route to high performance on JET

The capability of the Mk. I JET pumped divertor to give access to high performance plasma regimes has been successfully demonstrated. The considerable flexibility afforded by the divertor coil configuration and plasma position control system, together with operation of the torus cryo-pump, have facilitated a very extensive programme of experiments to determine optimum scenarios for maximising the total neutron emission from D-D reactions, fusion product n(D)(0)tau(E)T(i)(0) and equivalent Q(DT). Progress towards sustainable steady-state conditions at high fusion performance is also discussed.