Studies of cancer among Chinese and Japanese in the U.S. and homeland counterparts are conducted to ascertain the transitional effect at geographical and generational (nativity) levels, and to elicit clues to the mapping out of cancer prevention and control programs for U.S. Orientals and other populations. The past limitation on U.S. Chinese studies was resolved by the release of the 1975 PRC national mortality survey findings. Studies include: A study of cancer mortality among the Chinese in the U.S. (by nativity), Hong Kong, and Guangdong Province in the PRC was undertaken to examine migration effects because the majority of U.S. and Hong Kong Chinese originated in Guangdong. A second project, based on a similar hypothesis of the first study, was initiated comparing cancer mortality in Taiwan province and Singapore with that for Fujien province. A third study analyzes the incidence, mortality, and survival statistics on Chinese and Japanese groups in the SEER areas of San Francisco and Hawaii with a comparison of incidence in Los Angeles. Emphasis is placed on inter-community differences, on which future community specific cancer control and prevention programs may be used. Future plans include: extending the 1960 U.S. data and comparable statistics on Asian Chinese for a two decade trend analysis; acquiring local dialect data in Fujien, for comparison with the sub-population groups in Singapore; initiating field studies on life style changes in relation to cancer control and prevention.