Michael Thomas Hannan (born July 14, 1943) is an American sociologist who serves as the StrataCom Professor of Management at Stanford University, where he is also a professor of management at the Stanford Graduate School of Business.
Hannan was educated at the College of the Holy Cross, where he received a Bachelor of Arts (B.A.)
He pursued graduate studies in sociology at the University of North Carolina at Chapel Hill, earning a Master of Arts (M.A.)
His main contribution is introducing fuzzy concepts to the study of industry and population boundaries.
With his co-authors, Gael Le Mens, Greta Hsu, Balázs Kovács, Giacomo Negro, László Pólos, Elizabeth Pontikes, and Amanda Sharkey, they published a book on this topic: Concepts and Categories: Foundations for Sociological and Cultural Analysis.