The Alaska Native Tumor Registry includes data from 1969 to the present. This report provides incidence rates over the thirty year period, 1969 through 1998, and compares trends over time for Alaska Natives (AN) with those of US Whites and Blacks. To examine current rates, average annual age-adjusted incidence rates for AN for 1984-98 are compared with US Whites. Data from the registry document numerous differences in rates of occurrence of specific cancers compared to US Whites and Blacks. Studies of these differences may provide clues to the causes and risk factors for the cancers. Most importantly, these data show that although cancer was considered a rare disease in the Alaska Native population as recently as the mid-twentieth century, the incidence rate for all cancers combined among Alaska Natives is now as high as that of US Whites, and even higher in women. On the other hand, despite relative differences in rates, the most frequently diagnosed cancers among Alaska Natives are the same as US Whites. Cancers of the lung, colon/rectum, breast, and prostate are most frequently diagnosed among Alaska Natives and in the U.S. These four cancers comprise over 50% of all diagnosed invasive cancers. Cancer of the lung is almost entirely preventable by eradication of tobacco use. Screening and early detection have been proven to reduce mortality for cancers of the colon/rectum and breast. Primary and secondary prevention of these cancers could markedly improve morbidity and mortality.