The use of abbreviated versions of literary works from all fields of knowledge, from botany to the whole work of a historian such as Livy, was extremely common in Antiquity. These digests had various forms, ranging from “summary” (periochae) to the selection of abstracts (epitome), and passing by paraphrase; the absence of any theoretical framework, in the Greco-Roman world, explains such diversity. The contributors to this volume have been interested in studying specific cases of ancient abstracts, by questioning the different practices at work in scientific and technical works (medicine, astronomy, history) and in the rhetorical and academic context (poetry, school commentaries). They notice how surprising could be the ancient use of summarizing for the modern scholars. Indeed, ancient Greek and Roman scholars, in the writing of a book, did not hesitate to draw from summaries and not from integral works; others allowed themselves to add elements to the sources they were shortening, or even to “reinvent” the work they were summarizing. In the school context, abstracts had a particularly important role, of which ancient epitomators were often perfectly aware: deletions and modifications show particular attention to the readership, and the summary has its own issues in the transmission of all forms of literature.