Taxanes (paclitaxel and docetaxel) are antimicrotubule agents used in the clinical practice for the treatment of solid tumors. The molecular mechanisms of taxane-dependent cytotoxicity are only partially known. In vitro, different modes of action have been established for paclitaxel according to its concentration. A similar phenomenon has been shown for other microtubule-stabilizing drugs, including docetaxel. Recently, we described two different forms of mitotic exit in breast cancer cell lines exposed to docetaxel. The causes and consequences of the dual mechanism of cytotoxicity of this agent are discussed here.