AIMS: To compare the prevalence of diabetes in adults in small and medium sized towns in a part of rural Victoria MATERIALS AND METHODS: Participants were usual residents, aged >or=25 years, from randomly selected households in the crossroads undiagnosed disease study (CUDS: six small rural towns and their regional center in rural Victoria). Response rates to an initial census at the household and attendance at a subsequent biomedical examination involved were 70% and 61% (1454), respectively. All non-diabetic participants had an oral glucose tolerance test. RESULTS: Prevalence of diabetes, IGT, IFG were 7.3 (5.5-9.5)%, 6.9 (5.1-9.9)% and 3.2 (2.0-4.7)% respectively in the regional center and 8.9 (6.9-11.1)%, 4.9 (3.5-6.7)%, 3.0 (1.9-4.5)% in the Shire Capitals. Overall, 31/118 (26.3%) of those with diabetes were previously undiagnosed. Most (83.9%) of those with undiagnosed diabetes remembered having been screened for diabetes in the previous 2 years. Overall screening rates for diabetes were higher than across Victoria as a whole. CONCLUSIONS: The prevalence of diabetes has probably doubled over the last 15 years in this area. Undiagnosed diabetes is less common than expected, possibly as a result of a more vigorous approach to screening in general practice and in spite of the lower numbers of GPs in the area.