With his Sententiae, diuisiones, colores rhetorum et oratorum, published around 30 CE, Seneca the Elder, father of the stoic philosopher Seneca, produced an anthology of excerpts from declamations (forensic or deliberative mock-speeches) by 116 different declaimers who lived during the reigns of Augustus and Tiberius. By quoting these declaimers, Seneca intended to offer an informed and critical view on their qualities and defects, and to memorialize the emerging literary genre of declamation. But his text also lends itself to a more social reading. By mining the Sententiae, divisiones, coloresfor mentions of direct contacts between declaimers, and applying the methodology of network analysis, it becomes possible to read the anthology as a depiction of a structured intellectual milieu. The aim of this article is to identify and reconstruct the social relationships within the declamatory world described by the anthology, by exploiting the two kinds of links which emerge in Seneca’s quotes and comments: relationships fueled by criticism (where one declaimer assesses the performance of another) and relationships based on competition or imitation (where one declaimer builds on the production of another). After assessing the goals and biases of Seneca and their impact on his depiction of the declamatory milieu, this article expounds a method for 1) identifying concrete links between declaimers with a reasonable degree of certainty, 2) building a set of usable data based on these findings, and 3) assessing the meaning of the expected results in view of the incompleteness of the anthology. It then reconstructs and plots two declamatory networks (criticism, competition), and uses them to identify the central figures and to describe the relational structures of the Roman declamatory world depicted by Seneca.