The concurrent diagnosis of breast cancer and pregnancy is a challenging clinical situation that historically has placed the welfare of the mother in conflict with that of the fetus. Modified radical mastectomy, the preferred surgical option in women with breast cancer during pregnancy, can be accomplished with minimal fetal risk. Although breast-conserving surgery (lumpectomy or quadrantectomy) can be performed, the radiation therapy required to complete local therapy for the breast must be delayed until after delivery because of the risks associated with fetal exposure to radiation. Although much of the literature on the pharmacologic treatment of breast cancer during pregnancy is anecdotal, recently published data from our institution support the premise that breast cancer can be treated safely during the second and third trimesters of pregnancy with combination chemotherapy consisting of 5-fluorouracil, doxorubicin, and cyclophosphamide (FAC). Therapeutic abortion does not appear to improve survival for the mother, but it may be an option if maternal health is jeopardized or fetal anomalies are seen or suspected.