Contemporary society has the flows of information as one of it main characteristics and the information and communition technologies (ICTs) as one of its axes. In this context, the paradigm of networks has a special relevance, both for it qualities (the network society is a powerful metaphor) and as an analytical tool. It is the point we develop in this article, from a conceptual and methodological point of view, from what we discuss some study cases our group has develop on the use of ICTs and the construction of socio-technical networks.