Diabetes increases the risk of periodontal disease, but information from the tropics is lacking, and the relationship between periodontal disease and glycaemic control is uncertain. We examined 23 type 2 diabetic patients in a rural and resource-poor area of South Africa. Mean age was 59 ± 10 (1SD) years, and diabetes duration 6 ± 6 years. In all,11 were 'well controlled' (glycosylated haemoglobin (HbA 1c ) <8.0%, mean 6.5%), and 12 'poorly controlled' (HbA 1c >8.0%, mean 13.0%). Periodontal disease was more common in the poorly controlled group (42% versus18%, P <0.002). We conclude that dental health is poor in type 2 diabetic patients in rural Africa, and that periodontal disease is closely related to glycaemic control. Improved dental and diabetes care is needed in such communities.