Diabetes mellitus is classified into two major categories: type I, which is insulin dependent, and type II, which is not. Insulin resistance in type II diabetes may be related to impaired receptor binding in some forms of the disorder. In the past, diabetes in pregnant women resulted in high rates of maternal and infant mortality. During the past 10 years, however, better management of maternal diabetes has led to a significant sharp reduction in maternal and fetal morbidity and mortality. The long-term outcome of insulin-dependent diabetes remains gloomy, probably because adequate control of the disease has rarely been achieved. Recently, more stringent efforts have been made to achieve tighter control. Frequent monitoring of blood glucose levels at home and use of constant infusion insulin pumps may help to achieve this end until successful islet transplantation is feasible.