Ce volume présente les résultats du̕ne recherche internationale sur les contacts entre la communication orale et la communication écrite menée dans le cadre du projet interdisciplinaire ±Homo legens».How can we uncover the traces of oral culture in medieval sources when the oral matter we possess survives only in written form? Is it the case that only the written persists while the oral is lost? What was the status of orality in medieval society? The studies in this volume (five chapters in French and two in English) examine the links between the oral and the written traditions in medieval literature. They do this by means of the analysis of literary sources from very diverse backgrounds, both geographically and linguistically speaking: the investigation ranges from medieval Spain, through the Byzantine Empire and the Crusader states, to late medieval and early modern Turkey. This interdisciplinary enquiry by an international group of scholars enables us to define the modes of transmission of medieval texts and how they were memorized as well as to decipher how they were read and appropriated. In addition, the book suggests a methodological basis for research into indices of orality and for analysis of the intertextual links between literary works. This enquiry, undertaken within the framework of the international Homo Legens project, provides an efficacious tool for the study of the practices of reading and writing.