An introduction arrangement for a fenestrated or branched stent graft (13) intended for deployment into the lumen of a vessel having a blind vessel extending from it. The introducer (1) has a distal end intended to remain outside a patient in use and a proximal end with a nose cone dilator (11) and an arrangement to retain the branched stent graft distally of the nose cone dilator. A sheath (15) on the introducer extends over the branched stent graft to the nose cone dilator. An indwelling catheter (22) extends from the distal end of the introducer and enters the fenestration or side arm and through to the nose cone dilator, the indwelling catheter has a guide wire (29) extending through it. The guide wire can be extended beyond the nose cone dilator in use before the sheath is withdrawn from the branched stent graft so that it can be snared from the contra-lateral artery.