Ever since breast cancer has become looked upon as a local and simultaneously a systemic disease, local treatment has become ever less radical. Today, some 70% of all mamma carcinomas can be treated with breast-preserving techniques. Following pre-operative downstaging by primary neoadjuvant chemotherapy, even the majority of large tumors can be managed with conservative surgery. With the exception of ductal carcinoma in situ (DCIS) axillary lymph node clearance is currently standard practice. For an assessment of nodal status, at least 10 lymph nodes must be obtained and examined histologically. The sentinel lymph node biopsy performed under study conditions should be left to experienced specialized centers. Postoperative irradiation of the preserved breast is an element of the overall concept of breast-preserving surgery. The spectrum of surgical options covers breast-preserving procedures, skin-preserving mastectomy and amputation, which cannot always be avoided. With regard to plastic reconstruction, a differentiation should be made between the possibilities for reconstruction during primary surgery and reconstruction at a later date. Since postoperative radiotherapy can considerably diminish the results of reconstruction, current tendency is towards secondary reconstruction.