Michael Hannan

Michael Thomas Hannan is an American sociologist, and professor of management at the Stanford Graduate School of Business, known for his seminal work in the field of organizational ecology. Hannan received his B.A. at the College of the Holy Cross in 1965 and his M.A. at the University of North Carolina, Chapel Hill, in 1968, where he also obtained his Ph.D. in sociology in 1970.

Hannan started his academic career as an assistant professor of sociology at Stanford University, where he got promoted to professor of sociology. In 1984 he moved to Cornell University, where he was appointed professor of social sciences. In 1991 he moved back to Stanford to become a professor of management and professor of sociology and, since 2015, emeritus.

Among others, he was awarded a Guggenheim Fellowship in sociology in 1987 and a Max Weber Award by the American Sociological Association in 1992 and 2002. Hannan and John H. Freeman were the first to formulate an explicit organizational theory about population ecology with a 1977 article in the American Journal of Sociology, which was a seminal work in the field of organizational ecology. This article proposed:

... [a] population ecology perspective on organization-environment relations... as an alternative to the dominant adaptation perspective. The strength of inertial pressures on organizational structure suggests the application of models that depend on competition and selection in populations of organizations. Several such models, as well as issues arising in attempts to apply them to the organization-environment problem, are discussed.

The scope of their organizational ecology theory ranged from the birth of new organizations (organizational founding), organizational growth, and organizational change to the death of organizations (firm mortality). Organizations compete in their environment, where processes like natural selection rule.