The Nobel Prize in Chemistry 1981 was awarded jointly to Kenichi Fukui and Roald Hoffmann "for their theories, developed independently, concerning the course of chemical reactions"

The Prizewinners' work aims at theoretically anticipating the course of chemical reactions. It is based on quantum mechanics (the theory whose starting point is that the smallest building blocks of matter may be regarded both as particles and as waves), which attempts to explain how atoms behave. Good theoretical models provide guidance for experimental researchers and save them time. Fukui's and Hoffmann's theories are milestones in the development of our understanding of the course of chemical reactions. This development has, however, by no means been brought to a halt by the prizewinning work. This work has provided inspiration for new lines of development. Fukui and Hoffmann are among the most active researchers in these areas today.