In the course of the 'War on Terrorism' the United States has been permitted to use Shannon Airport, Ireland and Irish airspace for the purposes of refuelling, stop over, and fly over. Suspicion abounds that the United States has exercised these rights in relation to planes involved in 'extraordinary rendition' and, as a result, that Ireland is in breach of its obligation of non-refoulement under Article 3 of the European Convention on Human Rights. The Irish Government claims that it has received comprehensive and unequivocal Diplomatic Assurances from the United States that no persons have been, are being, or will be 'rendered' through Irish airspace and Shannon Airport and that these Assurances are sufficient to fulfill Ireland's Article 3 obligations, should they arise. This essay, forthcoming in the Irish Yearbook of International Law, examines two fundamental questions that arise in relation to this issue: (1) is Ireland's jurisdiction engaged as a 'transit state' under Article 1 of the ECHR, and (2) if jurisdiction is engaged, could the Diplomatic Assurances provided be sufficient for Article 3 purposes. Thus, this essay approaches the question of transit states' liability for 'rendition' from a doctrinal perspective that has, thus far, largely been under-explored.