The increasing diversity of New York's Latino population creates complex challenges for the health care provider and planner, such as how to plan for divergent health risks, disease patterns, and health behaviors. However, most research on Latinos has been done in the southwestern United States. This paper reviews the epidemiologic data published since 1980 on Latino groups in New York State. The review covers the following areas: maternal and child health, infectious diseases, depression, tobacco and substance use, chronic diseases, neoplasms, and mortality statistics. We compare New York data with studies done in other areas of the United States. We identify serious methodological shortcomings in the epidemiological assessment of New York's Latino population, including (1) imprecise definition of "Latino," (2) misclassification, (3) census undercount of minority groups, and (4) lack of data on socioeconomic status. We argue that the epidemiological and cultural diversity of Latino groups demands the inclusion of such variables as place of birth, length of stay, and language preference in research and service statistics. This would facilitate targeted program planning and help to determine environmental, sociopolitical, behavioral, and genetic influences on diseases.