A graduated arterial dilation balloon catheter, including an elongate catheter body for being introduced into an artery, and including a inflatable treatment zone section for being positioned in a section of an artery to be treated, a first, relatively small diameter balloon positioned distally in the treatment zone section, and a second, relatively large diameter inflatable balloon positioned proximally within the treatment zone section of the catheter body in longitudinal alignment with the first balloon and with the catheter body. A first dilation lumen is provided and extends in fluid communication along the catheter body between a first dilation port and the first balloon and a second dilation lumen is provided and extends in fluid communication along the catheter body between a second dilation port and the second balloon.