This volume situates itself at the intersection of two rapidly developing research areas: the investigation of Seneca’s reception of the Stoic tradition and the comparative study of the history of the emotions as culturally constructed phenomena. Impassiveness (apatheia) is usually regarded as the ultimate goal of the Stoic therapy of the emotions, since, by acting rationally, the Stoic wise person is expected to extinguish all emotions (pathē) except the ‘good’ ones (eupatheiai). Although a broad consensus exists on Seneca’s adherence to the Stoic worldview, no comprehensive study has ever been undertaken to assess the role of the notion of apatheia in the Senecan corpus in light of its connections with individual and social ethics, the physical constitution of the mind and the world, and the therapeutic task of philosophical writing. The contributions gathered in the present volume, written by a team of international scholars with recognized expertise in the area, aim to fill this gap by offering a fresh and critical overview of some of the most representative Senecan works, both in prose and in verse, which will be useful to classicists, ancient philosophers, cultural historians, and scholars of cognitive and psychological sciences.