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Book Reviews: Michael Hannan and John Freeman: Organizational Ecology 1989, Cambridge, Mass: Harvard University Press. 366 pages

Bocconi, Milan, Italy The first thing that must be said about Organizational Ecology is that it is the methodologically superb exposition of the core of one of the rare fully-fledged ’scientific research programmes’ in organization studies. The well-known model of population ecology, initially advanced by Hannan and Freeman in 1977 in the American Journal of Sociology, has germinated a far-reaching theoretical framework and a variety of empirical studies, which test the theory on populations of organizations in various sectors of socio-economic activity. The book is not a state of the art of organizational ecology though, but it is a ’summa’ of those theoretical models and empirical studies that have been designed by the authors themselves. The book clearly addresses an academic audience, and even within this audience, the reading will be enjoyed more by people who prefer abstract and concise argumentation rather than richness of examples and long discourse. Hannan and Freeman lead us through the Organizational Ecology research programme (O E hereafter) in three steps. The first section of the book discusses all the hypotheses and theoretical implications. The second section is a very dense list of the quantitative models used for estimating the basic rates of change in organizational populations, a section which gains vitality and interest if read in close connection with