An assembly for deploying a stent graft includes a stent graft (18). The stent graft (18) has a tubular structure and includes first (118) and second (120) end stents and at least one stent between the first and second end stents. The assembly also includes a plurality of constraining mechanisms arranged along the length of the stent graft (18). The assembly includes an actuation mechanism including a plurality of release wires or rods. Each of the constraining mechanisms includes a plurality of couplings to the release wires or rods, and the release wires or rods are operable to be withdrawn from the couplings to release the constraining mechanisms. The release wires or rods have ends which during withdrawal terminate at different longitudinal positions to release different couplings of each of the constraining mechanisms at different times so as to release each of the constraining mechanisms in stages.
