Extracting Ego-Centered Networks From Very Large Social Networks: This article presents a method at the intersection of macro and micro approaches in social networks. In examining ego-centered network, it proposes an approach to this type of study for very large networks. The calculation of several local indicators makes it possible to create aggregate statistics for each of the nodes of the network, which can then be seen as a corpus of ego-centered networks. An application is made on a network of telephone conversations between two million people, and a comparison is made with a classic ego-centered network study, based on an ethnographic research project. Social Networks, Ego-Centered Networks, Large Social Networks, Density, Communication Networks, Macro versus Micro, Qualitative Approaches [a corrected machine translation in English of this article is available on request from bms@reveus.org].