Despite recent developments in the treatment of breast cancer, metastatic breast cancer remains an incurable disease. Postoperative adjuvant treatment may improve the survival of a subgroup of node positive, Stage II breast cancer patients, but the proportion of failures is still high. Preoperative adjuvant chemotherapy, an example of a new approach in scheduling of available agents, is based on sound theoretical and experimental principles. In this report, the authors summarize the background data on the rationale for preoperative adjuvant chemotherapy and present preliminary results of this study in which preoperative treatment starting with one course of cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) was given to newly diagnosed patients with breast cancer. Analysis of the first 43 patients given such treatment has shown that the side effects were comparable to those seen in patients treated with conventional postoperative chemotherapy, and that the delay time between diagnosis and starting chemotherapy has been substantially reduced compared to the historic group of patients. Additional aspects of this study include the introduction of fine-needle aspiration as the only diagnostic method for obtaining the tissue diagnosis of breast cancer, as well as a more intensive interaction between the surgeons from private practice and the oncology institute.