The St Gall Tractate is the earliest medieval attempt at a comprehensive treatment of syntax. Dating from the tenth century and originating in the Swiss St Gall monastic school, the Tractate instructs readers in the art of analysing the construction of Latin texts. While its aim, the comprehensible oral delivery of Latin sentences, is purely practical, the Tractate also develops a penetrating analysis of language, anticipating by a full two centuries the exploration of syntax by the modistic grammarians. Its anonymous author demonstrates an encyclopedic knowledge of late classical, patristic and early medieval school texts; the topics addressed cover the entire scope of the liberal arts. This volume replaces the nineteenth-century edition by Paul Piper, and presents the Latin text from the Zurich, Zentralbibliothek C98 manuscript (not used by Piper) with English translation (by David Porter) on the facing page. A full set of textual and explanatory notes by both editors, and a scholarly introduction by Anna Grotans, setting the text in its cultural and intellectual context, complete the volume.