Stephan Irle has performed research in computational chemistry and materials sciences in Germany, Austria, the United States, and Japan. He has been a founding principal investigator at the Institute of Transformative Bio-Molecules (WPI-ITbM) at Nagoya University and member of the Japanese “post-K supercomputer” support project. His specialty is the quantum chemical study of complex systems. Target areas are soft matter and biosimulations, excited states of large molecules, electrochemistry, catalysis and geosciences. Complementary studies of physicochemical properties, theoretical spectroscopy, and the development of methodologies including approximate quantum chemical methods accompany this research.