It is unusual to obtain responses after two different sequential regimens in patients with metastatic breast cancer. In this retrospective analysis, data were examined on 22 patients who had already received two or three different regimens for metastatic breast cancer before being treated with 100 mg/m2 docetaxel (or 75 mg/m2 if clinically warranted). 13 patients received three or more courses and 21 patients were assessable for response. 5 of 21 assessable patients (24%) responded for 3-11 months and a further 6 (29%) stabilised. Toxicity (WHO grade 3 and/or 4), principally neutropenia, stomatitis and fluid retention, occurred in 10 patients. We conclude that docetaxel is an active agent in heavily pretreated patients with metastatic breast cancer, but care should be taken to minimise side-effects in this group of patients.