With the majority of breast cancers in the United States diagnosed at an early stage, treatment is focused on cure and the prevention of relapse due to micrometastatic disease. Because systemic adjuvant therapy effectively prevents or delays some relapses and deaths in early-stage disease, this treatment approach has become widespread throughout most of the Western world. The mainstay of care for patients with breast cancer has become local therapy, consisting of surgery, radiation treatment, or both, along with adjuvant systemic therapy, which can include tamoxifen, combination chemotherapy, hormonal therapy, or a combination of these treatments. Despite this wide range of effective therapeutic interventions, therapy for metastatic disease remains focused on improving overall survival and maintaining quality of life. Future efforts are focused on improving current treatment options by optimizing dose regimens, developing effective chemotherapy combinations, using novel approaches such as HER2/neu antibody-directed therapies, and providing palliative care in the latter stages of disease.