An apparatus for crimping a radially expandable stent includes a pressure vessel, shaping balloon, and mandrel. The mandrel is configured to slidingly receive a stent thereon, and to be slidingly advanced into the pressure vessel. The shaping balloon is inflated to radially compress the stent onto the form of the mandrel; such compression need not be uniform. Pressurization of the shaping balloon facilitates the expansion of the balloon to achieve compression of the stent, with depressurization of the shaping balloon causing the balloon to return to an unexpanded state.