We investigated whether paclitaxel was active in AIDS-associated Kaposi's sarcoma. We gave 135 mg/m2 intravenously over 3 hours every 21 days. Follow-up is available on the first 20 patients, most of whom had advanced Kaposi's sarcoma and severe immunocompromise. Neutropenia was the most frequent dose-limiting toxic effect; novel toxic effects included late fevers, rash, and eosinophilia. Creatinine increased in 2 patients and 1 patient had cardiomyopathy. There were 13 partial responses (65%, 95% CI 41-85%). All 5 patients with pulmonary involvement responded. Paclitaxel appears to be active against Kaposi's sarcoma as a single agent. Further studies, including a randomised trial, are warranted.