Active specific immunotherapy, or the use of tumor 'vaccines', attempts to stimulate the patient to reject his or her tumor. Nowhere has this approach been utilized more than in melanoma, often with encouraging results. The best results have occurred in the setting of minimal residual disease after resection of the primary tumor and involved lymph nodes, but responses have also been obtained in disseminated disease. Prolonged survivals of several years have been achieved in both settings, particularly the former, with little toxicity attributable to the treatment. Genetic and biochemical approaches promise considerably improved preparations of 'vaccines', with defined components and improved activity within the immediate future.