This work covers the history of the text of the invectives of Sallust against Cicero and of Cicero against Sallust. Though these speeches seem unsophisticated to some, they are in fact of considerable importance. The question of the authenticity of both invectives, especially of the invective against Cicero, considered in the book diachronically, has long troubled scholars, commencing with Quintilian's quotation from the text as though it were authentic. This dispute continues down to our own time. In all probability, both invectives are a product of the rhetorical schools of Rome, as students at such schools might have been set the task of writing a speech against Cicero imitating Sallust, or of responding to Sallust in the style of Cicero. Thus, we possess a sample of rhetorical school exercises, preserved due to their similarities to the prototypes on which they were modelled. The work covers: the full manuscript tradition of the text and also the history of the changes which arose during its transmission, the history of the printed text and the text itself with an apparatus criticus and also a translation. This work should be of interest to classicists, philologists interested in the history of medieval and renaissance texts, and also to those erudite readers concerned with rhetorical style and the functioning of the rhetorical schools of Rome.