Abstract
For a physicist, fusion research has been since its inception an applied physics programme, with a big dream: developing fusion as a reliable source of energy using the fusion reaction between light elements. The fusion reaction, where two light nuclei fuse together, produces vast amounts of energy compared to the fuel quantity. This is the reaction that powers the sun, and the harnessing of fusion energy means being able to reproduce the conditions of a sun on a portable scale on earth. To do so, as in most “big science” projects, the progress in the physics understanding has to go hand in hand with the development of daring novel engineering and technical solutions. This talk will present the basics physics problems to be solved, together with the accompanying technological advances that are making a reality of the ITER experiment, and the path still to be covered for future reactors.