Socio-semantic networks involve agents creating and processing information: communities of scientists, software developers, wild Contributors and webloggers are, among others, examples Of Such knowledge networks. We aim at demonstrating that the dynamics of these communi ties can be adequately described as the coevolution of a social and a socio-semantic network. More precisely, we will first introduce a theoretical framework based on a social network and a socio-semantic network, i.e. an epistemic network featuring agents. concepts and links between agents and between agents and concepts. Adopting a relevant empirical protocol. we will then describe the joint dynamics of social and socio-semantic structures, at both macroscopic and microsc...