Professor Arnold L. (Arny) Demain's historical position in the rise of industrial microbiology and biotechnology.

This perspective text focuses on the pivotal role and historical position that the late Prof. Arnold L. (Arny) Demain has taken since the 1950s in the rise and impact of the field of industrial microbiology and biotechnology. His drive toward academic research with industrial potential-first at Merck & Co. and later at MIT-, his feeling for establishing cordial personal contacts with his students and postdocs (Arny's Army) and his ability for worldwide networking are outlined here, intertwined with the author's personal experiences and impressions. His scientific output is legendary as to research papers, comprehensive reviews, books, and lectures at conferences worldwide. Some of his research experiences in industry and academia are mentioned in a historical context as well as his relentless efforts to advocate the importance and impact of industrial microbiology and biotechnology as an essential green technology for our planet Earth.