Research is considered as a major component of innovation and a key to the development of modern societies. However, fundamental research, which essentially aims at improving our understanding of Nature, is often questioned about its specific role. In this paper, arguments of ‘general interests’ in support of fundamental research are presented to contribute to the science-policy debate. Beyond a notable return on investment, now acknowledged by most economists, a number of positive societal impacts of fundamental research can be underlined. Fundamental research helps society as a whole, as well as individual firms, to keep options, possible scenarios and choices open (e.g. in relation with sustainable development), to maintain a good capability for top-level scientific expertise, to develop conditions favourable to scientific and technological breakthroughs, to ensure training at the highest possible level and also to guarantee access to, and free circulation of, the most valuable information. Finally, fundamental research may contribute to a better structural link between science and society.