Paclitaxel, a chemotherapeutic drug isolated from the Pacific yew, was approved for the treatment of metastatic breast cancer in 1994 and remains one of the most important agents in the treatment of patients with this disease. It is currently approved for the adjuvant treatment of node-positive breast cancer, administered sequentially after a standard doxorubicin-containing regimen, and for metastatic disease after failure of combination chemotherapy or relapse within 6 months of adjuvant chemotherapy. In this article, data on the pharmacology, clinical efficacy and safety of paclitaxel for the treatment of breast cancer will be reviewed.