Health care availability and living conditions have improved substantially for American Indians in New Mexico over the past quarter century. To investigate the impact of these changes on health statistics, we examined mortality data collected from 1958 to 1987 for American Indians in the state. We analysed the data for all causes of death combined and for specific causes, and compared these data with figures for nonHispanic whites in the state. Age-adjusted mortality rates were calculated for 5-year periods for each ethnic-gender group, using denominators from US Census reports. Mortality rates for all causes combined did not improve significantly for American Indian males from 1958 to 1987, although the rates for American Indian females showed an 8% decline. Infectious disease-related mortality rates for American Indians decreased dramatically over the 30-year study period; however, mortality rates for cancer and diabetes increased over the 30-year period. Mortality rates for injuries and alcoholism among American Indians increased greatly from 1958 to 1977 and then declined later in the study period, but they were consistently higher than rates for whites. The study indicates that several chronic diseases remain of major public health importance for New Mexico's American Indian population.