Demetrias has yielded the largest number of terracotta figurines of a popular iconographic type of the Hellenistic period: the ‘kausia boy’, shown standing, dressed in the chiton, chlamys, kausia and krepides. The rediscovery of the material from A.S. Arvanitopoulos’ excavations at Demetrias in the early twentieth century has provided an opportunity to reassess the significance of this iconographic type in the city and in the wider Hellenistic world. Combining and comparing the material from Arvanitopoulos’ excavations with that from other excavations in the city by the German Archaeological Institute and the Ephorate of Antiquities of Magnesia, it is now clear that the kausia boy figurines from Demetrias were discovered in various contexts, including sanctuaries, graves and the foundations of the royal palace (Anaktoron); the largest number was found in the sanctuary of Pasikrata. It has been possible to identify more than ten technical types, confirming the importance of these figures in the coroplastic production of the city. This paper also discusses the iconographic types of the ‘shepherds’, kausia-wearing boys holding the syrinx and the lagobolon, as well as the animal-carrying boys, since they too are wearing the same attire, and are mechanically related to the simple kausia boy types. The study of Demetrias’ specimens, combined with the study of the distribution of these iconographic types in the Hellenistic world and the relevant iconographic, literary and epigraphic evidence enable its reinterpretation.