Factors affecting the growth of 67 diabetic children were analysed retrospectively. The effects of age, sex, three year average glycosylated haemoglobin (HbA1) levels, time since diagnosis and age at diagnosis were assessed on the change in the child's height standard deviation score (SDS) over three years, as well as the change in height SDS from diagnosis. No correlation between these factors was noted over a three year period; however, there was a strong correlation (p less than 0.001) in the change in height SDS from diagnosis with the age of the child and time from diagnosis. Multiple regression analysis revealed that the younger the child at original diagnosis, the less the height SDS loss, and also that in younger children the age of the child and not the time from diagnosis was the more important variable in deciding the loss in height SDS. No correlation existed between HbA1 levels and either the short or long term growth of patients in this study.