A stent or stent-graft deployment device and in particular a pusher member forsuch a device are disclosed. The pusher member (62) is provided with a reducedouter diameter section (64) and a pusher head (60). The reduced outer diametersection (64) reduces the thickness of the wall of the pusher member (62), withthe result that the rigidity of the pusher member (62) is reduced at its distalend. This reduction in rigidity reduces the transition in flexibility betweena guidewire catheter (24) extending through and beyond an inner channel of thepusher member (62) and the distal end of the pusher member (62). Thus, there isa gradual change in rigidities at the junction between these two components,which can reduce the possibility of kinking.
