In this chapter we deal with the preservation and transmission of Greek and Latin letters in Late Antiquity. We begin with the problematic of letter-collections, in which a large number of letters has come down to us, before addressing the transmission of letters in translations, many of which were made in order to save their authors from damnatio memoriae. Missing letters then occupy us, whether their absence is documented or can be read between the lines or whether they were never written at all. In this section we discuss the problematic correspondence between Augustine and Jerome, a cause célèbre in late-antique epistolographical studies and an example of what could go wrong in correspondences of the time, before addressing the question of forgeries, tampering of documents transmitted from author to recipient, and pieces that have some down to us with erroneous attributions.