Harrison C. White holds a Ph.D. in Theoretical Physics from the MIT and a Ph.D. in Sociology from Princeton University and is the Giddings Professor of Sociology at Columbia University, in New York. He is well known for his work on social network analysis and the structure of production markets (Markets from Networks, Princeton University Press, 2002). He is just finishing a massive rewrite and extension of his 1992 book, Identity and Control. It is to be translated by Michel Grossetti and Frédéric Godart into French.