MONDADA Lorenza - Sequential organization of linguistic resources in joint elaboration of descriptions. This paper concerns the ways that speakers jointly construct their descriptions of facts, events and objects. Analyzing them means studying speech-turns and the specific exploitation of linguistic resources (what we call "Grammar-for-interaction"). Descriptive activity takes shape especially through the joint construction of statements, which allows one to reflect on the way the turns and the "turn constructional units" are organized as units arising from the interactional achievements of the speakers. Several observable cases in point are described, as well as their effects in terms of how the exchange is organized, concentration, help, more or less shared knowledge, agreement and disagreement, or co-belonging of speakers.