Breast cancer is common in older women, and the segment of the U.S. population aged 65 years and older is growing rapidly. Consequently, awareness is increasing of the need to identify breast cancer treatment recommendations to assure optimal, individualized treatment of older women with breast cancer. However, the development of these recommendations is limited by the heterogeneous nature of this population with respect to functional status, social support, life expectancy, and the presence of comorbidities, and by the underrepresentation of older patients with breast cancer in randomized clinical trials. The NCCN Breast Cancer in the Older Woman Task Force was convened to provide a forum for framing relevant questions on topics that impact older women with early-stage, locally advanced, and metastatic breast cancer. The task force is a multidisciplinary panel of 18 experts in breast cancer representing medical oncology, radiation oncology, surgical oncology, geriatric oncology, geriatrics, plastic surgery, and patient advocacy. All task force members were from NCCN institutions and were identified and invited solely by NCCN. Members were charged with identifying evidence relevant to their specific expertise. During a 2-day meeting, individual members provided didactic presentations; these presentations were followed by extensive discussions during which areas of consensus and controversy were identified on topics such as defining the "older" breast cancer patient; geriatric assessment tools in the oncology setting; attitudes of older patients with breast cancer and their physicians; tumor biology in older versus younger women with breast cancer; implementation of specific interventions in older patients with breast cancer, such as curative surgery, surgical axillary staging, radiation therapy, reconstructive surgery, endocrine therapy, chemotherapy, HER2-directed therapy, and supportive therapies; and areas requiring future studies.