The aim of this study was to evaluate the effect of home blood glucose monitoring on diabetic complications and metabolic control. Forty Chinese and Indian patients participated in the Diabetic Society of Singapore National Home Blood Glucose Monitoring (HBGM) Programme. The clinical progress, the blood glucose and glycosylated haemoglobin concentrations, and the platelet aggregation of the aforementioned patients were studied over a 6-month period; the results were compared with those from a matched, albeit smaller, control group of 18 diabetic patients who were on treatment but not in the HBGM programme. At the end of the six month period, three patients in the control group showed clinical deterioration of peripheral neuropathy in contrast to one patient on HBGM. Due to the small number of patients, the difference in the findings was not statistically significant. Patients on HBGM demonstrated significant improvement in mean grouped blood glucose profile values, 135 +/- 8 to 118 +/- 5 mg/dl, p less than 0.01, and glycosylated haemoglobin levels, 10.3 +/- 0.4 to 9.3 +/- 0.3%, p less than 0.01. The platelet aggregability was unchanged. In contrast, patients in the control group developed a significant increase in platelet aggregation (30 +/- 4% to 37 +/- 5%, p less than 0.05), although the blood glucose and glycosylated haemoglobin concentrations were not significantly altered. This study demonstrated that patients on a six-month HBGM programme were able to achieve improved glycaemic control associated with a trend towards decreased deterioration of diabetic neuropathy and platelet aggregability.