Background: Increases in the incidence of malignant melanoma have been among the largest of all cancers in the United States. Objective: We report updated trends in melanoma rates among the US white population. Methods: Incidence and mortality rates were calculated for 1973 to 1994. Trends were examined with stratification by state, age, and sex, and by anatomic site, stage, and melanoma thickness at diagnosis. Results: Melanoma incidence and mortality rates increased dramatically from 1973 to 1994, rising 120.5% and 38.9%, respectively. In recent years, however, rates for most age-sex groups appeared to stabilize or even decline. Male patients continued to have higher incidence and mortality rates than female patients, but for both male and female patients the largest increases by site were for the trunk. A large proportion of melanomas were detected in the local stage and with a thickness less than 0.75 mm. Conclusion: Prevention of sun exposure is recommended to reverse the high incidence rates of melanoma.(J Am Acad Dermatol 1999;40:35-42.)