Primary sarcoma of the breast is an extremely rare and heterogeneous disease. The rarity of this tumour limits most studies to small retrospective case reviews and case reports and has made clinicopathological study difficult. This article reviews the current literature on the diagnosis and management of breast sarcoma. The optimal treatment of breast sarcoma involves a multidisciplinary team prior to the initiation of treatment. Patients with tumours less than 5 cm that are easily resectable should undergo complete resection to the extent required to provide negative surgical margins. Negative surgical margins are more important for local recurrence and overall survival than the extent of surgical resection. Thus, neoadjuvant chemotherapy should be considered in order to shrink the tumour and help obtain negative surgical margins. Whether chemotherapy is indicated is primarily determined by tumour size. There is evidence that tumours larger than 5 cm are associated with an elevated risk of systemic failure and a poor prognosis. After surgical resection, patients with chemosensitive tumours should undergo additional adjuvant chemotherapy to treat micrometastatic disease. Radiation therapy should be used to improve local control in cases in which the tumour is larger than 5 cm and in cases with positive surgical margins. We propose to treat the patients according to the clinical practice guidelines in use for soft tissue sarcomas and address them to a reference centre for sarcoma. The appropriate treatment of breast sarcoma requires a multidisciplinary team approach necessitating experienced sarcoma surgeons, pathologists, radiotherapists and medical oncologists. Treating rare tumours in the same place should permit us to standardise pathological data and to include patients into multicentric radiotherapy or chemotherapy protocols to improve overall survival.