The JET experimental programme in 1991 has again embraced a wide variety of experiments and has included the testing of plasma-facing components, the development of new operational scenarios, studies of divertor and edge processes, the investigation of global and local current-drive techniques, the pursuit of high fusion yield, as well as the exploitation of new enhancements of the JET subsystems. A broad range of tokamak physics studies addressing such areas as MHD stability, impurity generation and control and confinement and transport issues has continued in parallel.