A substantial body of experimental evidence suggests that local application of radiation at sites of angioplasty or stent implantation prevents neointima formation. Recent initial clinical studies report a significant reduction in clinical restenosis rates when gamma emitting radiation sources are used to treat the site of coronary intervention. Because of the energy of therapeutic gamma sources and the shielding requirements, it would be far preferable to deliver ionizing radiation using a local beta emitter. This report discusses a number of the physical, biological, and technical parameters involved in radiation from a balloon angioplasty catheter filled with a beta emitting radioisotope solution.