The invention is an enhanced vascular dilator that eliminates the vascular injury caused by the size mismatch between vascular introducer sheaths and vascular dilators, as the two are advanced into a blood vessel. The invention provides a “shoulder” to match the diameter of the introducer sheath so that there is a smooth transition, without size mismatch, between the dilator and the introducer sheath. The invention allows the dilator to be withdrawn in segments from the introducer sheath. This is especially valuable to reduce vascular injury when using large-bore introducer sheaths for interventional procedures including transcatheter valves and endografts.