My thesis entitled ‘The Origins and Development of Linguistic Atticism’ deals with the linguistic debate around the idea of ‘correct Greek’, and especially with the origins and the development of a movement known as Atticism, which promoted the Attic of the fifth century BCE as the correct language through the means of lexica. My research demonstrates that Atticistic tendencies, which are conventionally considered a typical product of the second century CE, already informed Greek linguistic approaches from the fifth century BCE. This changes our approach both to Hellenistic and Imperial sources, which played a much more important role in the consideration of Attic as the correct language than is presently realised. The aim of this thesis is to analyse the types of linguistic approach that brought about the Atticistic mindset, as it was expressed in the Second Sophistic with the production of Atticistic lexica. The first chapter deals with Atticistic lexica produced in the second century CE. In this chapter I analyse certain mechanisms in the approach to Attic and koine. The purpose is to define a frame in which to analyse material from the Hellenistic and Classical age. The second chapter is dedicated to the analysis of the Classical material focusing on the status of Attic in the fifth century and the flourishing of certain purist tendencies that foreshadow later Atticistic developments. The third chapter deals with the Hellenistic age which represents the bridge between the Classical and Imperial ages in the consistent development of a series of linguistic approaches through a systematic formulation of the idea of norm and canon.