In 2015, after 44 years of service, Dr. Duff formally retired from the department. He maintains a limited research agenda with several current and former M.S. and Ph.D. students. Dr. Duff has published over 180 journal articles and conference papers and served as an associate journal editor. He created 15 new courses, taught 26 different courses, and has been the major professor for over 60 masters students and 25 Ph.D. students. Dr. Duff headed the department’s Industrial Engineering and Operations Research and Engineering Management undergraduate and graduate programs for 36 years, chaired the college Systems Engineering and Optimization committee for 15 years. He served on university committees for nine years, where he established the university’s current Latin Honors awarding procedures and was a primary contributor in establishing the initial university formal procedures on academic dishonesty. He organized and managed International Energy Agency Solar Heating and Cooling Task programs and projects for 19 years. Dr. Duff also spent seven years at the University of Chicago Department of Physics Enrico Fermi Institute and a year at the Philips research laboratory in Aachen, Germany. He started two companies, helped start two others, and served on the board of directors for four companies and two academic societies.