One of the three possible long term options for providing mankind with sufficient energy is controlled thermonuclear fusion. It is still in a stage of basic research, i.e. the conditions for producing a high fusion reaction rate for a sufficiently long period of time have not yet been mastered. However, the relevant figure of merit (the product n·t·T of particle density, energy confinement time and temperature) has been improved by almost four orders of magnitude over the past 20 years. Among the various approaches towards this goal the method using magnetic confinement of very hot plasmas is in the lead, and within this research line the tokamak devices have been most successful. A present, the largest of the tokamak experiment is JET which is operated by the European Community (in England). The plasma parameters such as density and temperatures which have been reached, as well as the observed and yet unsolved problems, are close to the regime of values needed in a fusion reactor. Among the recent advances the first time usage at JET of the real fusion reactants, deuterium and tritium, in some discharges stands out. In these pulses a significant amount of fusion power (1.7 MW) was generated. In the near future the research line with tokamaks will be pursued vigorously throughout the world, for example with further extensive research programmes on JET (EC), TFTR (US), JT-60 (Japan), ITER (world wide), and on numerous smaller devices.