The incidence of cancer of the cervix uteri in Khon Kaen Province is moderately high (age-standardised rate 16.8 per 100 000 person-years), with about a two-fold variation in incidence between different districts. Stage at presentation is considerably more advanced than in the United States and Europe, and there has been little change in incidence over the last 15 years. Currently, control of cervix cancer is through early detection and treatment. Screening programmes have, to date, been opportunistic, but a new national plan anticipates that all women will be screened six times during their lifetime. The results from Khon Kaen provide a benchmark against which the success of this policy can be evaluated.