A prospective 3-year survey of nonmelanoma skin cancer in Japanese-American residents of the Hawaiian island of Kauai was conducted beginning in January 1983. The crude rate for basal cell and squamous cell carcinoma was 123/100,000, 88 times higher than the corresponding figure from Japan. This discrepancy may be attributed to an increase in ultraviolet exposure due to lifestyle and latitude, but arsenic exposure may also have played a role. Nonmelanoma skin cancer in Japanese in Hawaii appears to be a significant problem that has not been appreciated because these malignancies are not reportable to tumor registries.