We hypothesize that changes in tumor gene expression profiles vary in response to different sequences and types of chemotherapy, and that gene expression changes will correlate with tumor response. We are also looking to correlate drug pharmacokinetics and treatment toxicity with genotype of drug metabolizing enzymes and tranporters.Patients with metastatic breast cancer and who have measurable primary breast tumor will be randomized to one of two alternating sequences of adriamycin and docetaxel. Serial tumor biopsies and plasma samples will be obtained for gene expression and proteomic studies to identify biomarkers that will predict for chemotherapy response.