Extensive clinical experience has been obtained with the antineoplastic agent vinorelbine (Navelbine; Burroughs Wellcome Co, Research Triangle Park, NC; Pierre Fabre Médicament, Paris, France) in Europe and elsewhere. This experience recently has been supplemented by three clinical trials of patients with advanced non-small cell lung cancer or breast cancer conducted in North America. Data from these trials indicate that vinorelbine is safe and well tolerated in the outpatient population. Granulocytopenia is the dose-limiting toxicity. Although the incidence of this condition is high among vinorelbine-treated patients, it is uncommonly associated with severe complications. Elevations in alkaline phosphatase levels are seen in the majority of patients, but this effect may be due in part to liver and bone metastases. Nonhematologic toxicities are mostly mild or moderate. Injection site reactions have been noted in some patients, but improved administration techniques may help reduce the incidence of this effect. Gastrointestinal and respiratory effects are seldom severe and usually respond to treatment. Drug-associated neurotoxicity occurs less often than with other commonly used vinca alkaloid compounds. Overall, vinorelbine is associated with few severe toxicities, which for the most part, are easily managed. Thus, this agent seems well suited for use in the outpatient treatment of non-small cell lung and breast cancers.