 Fleck was on the faculty of the Harvard Business School teaching first-year finance in the MBA Program, 1964-1966.From 1966-1970, he was professor and associate dean, Faculty of Administration Studies and director, M.B.A. program at York University.He has also taught, as a visiting professor, at the Keio University Business School of Tokyo; INSEAD (The European Institute of Business Administration in Fontainebleau, France) and the University of Western Ontario, as well as teaching courses in corporate finance, business policy and business/government relations.