All diabetics are at risk from the development of the specific and non-specific complications of the disorder. While good control with relative normoglycaemia may be beneficial, most of the emphasis on maintaining stricter blood glucose control has been aimed at the insulin-dependent diabetic. Seventy-four sylphonylurea-treated were observed for a year and their degree of control assessed and compared using simple clinical criteria, plasma glucose levels and haemoglobin A1c concentrations. Control was considered good in 55.4 per cent, 16.2 per cent and 14.9 per cent using each criterion respectively. Simple clinical assessment of control is therefore unlikely to achieve normoglycaemia in the majority of such patients. A more wide ranging assessment and a more aggressive approach to therapy may be desirable if better blood glucose control can be shown to produce a reduction in the significant morbidity and mortality in these patients.