Breast cancer is the most commonly diagnosed cancer among women in the United States. Approximately half of all patients diagnosed with early-stage breast cancer receive conservative breast surgery followed by consolidative radiation treatment. A number of technologic advances have been made in radiation therapy planning and treatment that minimize early and late toxicities and may improve treatment outcomes. Among these are (a) the treatment of patients with large or pendulous breasts or cardiopulmonary disease in the prone position, (b) intensity-modulated radiation treatment, which delivers precise, highly conformal radiation dose distributions within the breast by using computerized inverse treatment planning and intensity-modulated radiation beams to produce the required dose distribution, and (c) brachytherapy, which is the placement of a radioactive source within the lumpectomy bed. These advances are gaining national recognition and are available at many institutions. Nurses play a vital role in educating patients; therefore, nurses must have the information they need to inform their patients about these advances. The information in this article will allow nurses to help patients understand the anticipated treatment and related side effects and made informed decisions.