This thesis is a critical edition of the poems and the rosc found in the Middle Irish tale Airec Menman Uraird maic Coisse ‘The Strategem of Urard mac Coisse’. The tale tells of how the poet Urard mac Coisse seeks compensation from Domnall mac Muirchertaig, the tenth-century king of Tara, after the ransacking of his home by Domnall’s kinsmen. Since the poet does not want to directly accuse the king’s relatives of the crime, he invents an allegorical in-tale titled Orcain Cathrach Maíl Milscothaigh ‘The Plundering of Máel Milscothach’s Fort’. After the recounting of the tale which includes the reciting of four poems and a rosc, the king comes to understand, via an angel, that Máel Milscothach is actually Urard mac Coisse. The poet is then given full restitution. The tale is found in three manuscripts: Oxford, Bodleian Library MS Rawlinson B 512; Dublin, Royal Irish Academy MS 23 N 10; and London, British Library MS Harleian 5280. The tale has yet to be edited and translated in its entirety; consequently, this thesis partially fills this gap in knowledge via a critical edition of the poems and the rosc. Chapter 1 provides a literary background to the tale and discusses the following themes: the identity of Urard mac Coisse, the Tale-Lists, the role and skills of a fili ‘poet’, hospitality, allegory and etymology. Chapter 2 presents the critical edition of the poems and the rosc, completed with textual notes and translation. A discussion of the manuscripts, the language and dating of the text as well as editorial policies is included. This thesis provides a critically restored and normalised text based on the three extant manuscripts and discusses issues faced when editing a Middle Irish text.