Optimal regimen for therapy should lead to near-normal glycaemia in children with diabetes mellitus. Therefore normal or near-normal values of glycated haemoglobin (HbA1) during long periods seem to be very important for the assessment of the quality of metabolic control. However, reports published so far indicate that this goal for paediatric diabetology is currently not achieved in a considerable number of patients. We report on the results of HbA1-estimations in 76 children with diabetes mellitus during a one-year period. We found in 14 (18.4%) children HbA1-values within the normal range (mean + 2 SD) and in 25 (32.9%) children HbA1-values in the range below mean + 3.5 SD. The therapeutic goal near-normal glycaemia with HbA1-values below mean + 3.5 SD and probably no or only a small risk for diabetics to develop late vascular complications could be achieved in 39 (50.1%) diabetic children. Our results are compared with those published in literature and with current therapeutic regimens.