A multi-stage balloon catheter (20) has a deflated state, a first inflation state at a first pressure and a second inflation state at a higher fluid pressure. In the first inflation state, the multi-stage balloon has a plurality of bulb segments (42) separated by waist hoops (40) that allow the multi-stage balloon to conform to match the curvature of a passageway. When pressure is increased in the multi-stage balloon from the first inflation state to the second inflation state, the waist locations expand either by breaking or stretching the waist restraints or by overcoming expansion resistance incorporated into the balloon material at the waist locations. The multi-stage balloon catheter may be used to implant a stent (90) in a manner to conform and match a curved passageway rather than tending to straighten the passageway.