For the past decades the anthracyclines have been regarded as among the most active drugs for the treatment of metastatic breast cancer. However, the 5-year survival rate in patients with stage IV breast cancer continues to be below 20%, and new active drugs and drug combinations clearly must be explored. Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) has been demonstrated to be highly effective in treating patients with advanced breast cancer, including those with anthracycline-resistant breast cancer, a fact that has led to efforts to combine paclitaxel and anthracyclines. Several studies aiming to define the optimal dose and schedule of combination paclitaxel/doxorubicin have now been completed or are ongoing. Phase I/II studies have yielded encouraging preliminary response rates but quite variable toxicity profiles depending on the schedule used. These clinical trials involving combination paclitaxel/doxorubicin are reviewed, with special emphasis on the short-infusion trials.