Rural-urban comparisons of diabetes prevalence were made in the Polynesian population of Western Samoa. The prevalence of diabetes in the urban population was almost three times that in the rural (10.1% versus 3.6%). While the urban male and female subjects were significantly more obese than their rural counterparts, the difference in prevalence rate could not be wholly explained on this basis. Diabetes prevalence was still approximately double in urban subjects when we compared the rural and urban populations after removing the differences in obesity and age. The results suggest that, apart from age and obesity, other factors, e.g., differences in diet, physical activity, or stress (or a combination of these), may participate in the rural to urban difference in diabetes prevalence.