a delivery system for a stent includes a catheter having an elongated inner member and at least one flexible , longitudinally oriented outer member that is operably attached to the distal portion of the inner member . a stent is placed concentrically around the flexible outer member , near the distal end of the catheter . when the elongated inner member is retracted , the flexible outer member folds longitudinally adjacent to the lumen of the stent causing the stent to be deployed . another aspect according to the invention provides a method for delivering a stent to a treatment site within the vascular system .