The incidence of malignant melanoma continues to rise steadily in the United States, with approximately 40,300 new cases expected in 1997. A significant number of patients with deep primary lesions or regional lymph node metastases are at high risk for developing recurrent, metastatic disease despite adequate surgical intervention. Therefore, approaches to adjuvant therapy including immunotherapy, such as interferon, levamisole, and vaccines and chemotherapy and chemoimmunotherapy have been investigated in high-risk patients. The key adjuvant trials are reviewed, with emphasis placed on randomized trials. High-dose interferon-alpha has recently been shown to modestly improve disease-free and overall survival in a prospective randomized trial of high-risk patients and has been approved by the FDA for this indication. Vaccines, which currently remain experimental, may prove to be equally effective but less toxic options for adjuvant therapy. Also, the identification of more high-risk patients who might benefit from adjuvant therapy may be facilitated by sentinel lymph node biopsy and the reverse-transcriptase polymerase chain reaction for tyrosinase.