 For his graduate studies he moved to the Cornell University, where he obtained his PhD in Operations Research.Since the 1990s he has been awarded honorary doctorates by the University of Stuttgart in 1994, the University of Lodz in 2006, and the University of Waterloo in 2008.Kaplan joined the Harvard Business School faculty in 1984 after spending 16 years on the faculty of the business school at Carnegie-Mellon University, where he served as Dean from 1977 to 1983.