A catheter with two balloons for implanting a stent without flaring at the ends of the stent during implantation has an outer balloon overlying an inner balloon. The length of the inner balloon is shorter than the length of the outer balloon and shorter than a stent which is mounted over both balloons. Upon inflation of the inner balloon, the inner balloon expands only the center of the stent. After the center of the stent is expanded, further application of pressure bursts the inner balloon allowing application of pressure to the outer balloon. The outer balloon is then inflated, expanding the ends of the stent.