The Liber de munitionibus castrorum ("Book about fortifying a camp", as it is usually known) describes how to lay out a temporary camp for a Roman army on campaign, comprising three legions and associated troops of various types. It is our main source for many aspects of Roman military studies, as it includes descriptions of not only the major military unit types, but also the different methods of fortification. Only a single copy of the work survives, preserved in a sixth-century manuscript, and the Latin text is in poor condition requiring major emendation. Although German, French, and Italian editions have appeared at various times, this is the first English-language edition, in which a new Latin text is presented alongside an English translation. For comparison, interested readers will also find the original Latin text and all previously suggested emendations.