John Michael Harrison (born 1944) is an American researcher, known for his contributions to the theory of operations research, in particular stochastic networks and financial engineering.
He is currently the Adams Distinguished Professor of Management at Stanford University.
His research focused on stochastic modelling for business and led to influential results in option theory (with David M. Kreps, 1980).
More recently he has studied dynamic pricing and revenue management.
In 2008, Harrison was elected a member of the National Academy of Engineering for fundamental contributions to stochastic networks and financial engineering.