During a routine medical examination of 5280 government employees (2736 males, 2544 females; age range 17 to 66 years; 3386 Chinese, 1252 Malays, 508 Indians and 134 other ethnic groups) diabetes was found in 31 (0.59%). The prevalence was higher in males (0.95%) than in females (0.20%). The highest prevalence was in the age-group 50 to 59 years (5.4%); at ages 30 to 66 years, the overall prevalence was 2.18%. The prevalence of diabetes is higher in Indians (2.76%) than in Chinese (0.30%) and Malays (0.48%); the difference is statistically significant, as it also is in the age-group 30 to 66 years (Indians 6.36%, Malays 1.39%, Chinese 0.9%). Of the 31 cases, only four were previously known and only nine were overwieght. The possible reasons for the higher prevalence of diabetes in Indians are discussed.