Family physicians should be aware of the early signs of malignant melanoma, as well as measures that can be taken to prevent the disease. Etiologic factors for melanoma include sunburns, particularly those occurring early in life, giant congenital nevi, dysplastic nevi and the presence of numerous nevi. The four major subtypes of melanoma are lentigo maligna, superficial spreading melanoma, acral lentiginous melanoma and nodular melanoma. Diagnosis is based on excisional, incisional or punch biopsy. The crude five-year survival rate for malignant melanoma is 81 percent, but survival depends on stage of disease, anatomic site, the patient's age and sex, histologic factors and clinical subtype. Surgical excision is the usual treatment for primary melanoma. Surgery, radiation therapy and chemotherapy are used in the management of metastatic disease, but the prognosis following the development of metastases remains poor. Family physicians can affect survival rates by improving early detection, promoting patient awareness and self-examination, and encouraging regular physical examination of patients who are at increased risk of melanoma.