The aim of the diabetes specialist is to provide a service to the pregnant diabetic woman so that she will present to her obstetrician with such well-controlled plasma glucose levels that her pregnancy will proceed without any diabetes-related problem, and she will be delivered of a normal baby, of normal size, at the normal full-term gestation, by the normal route. There are some problems in achieving this aim. The exact definition of hyperglycaemia in pregnancy is still a matter of dispute. Screening methods to identify the problem differ widely. Many centres have developed joint diabetes/antenatal clinics, but there are practical problems with such an approach. Pre-pregnancy counselling, and discussion of contraceptive measures is an important task for the diabetologist and requires up-to-date knowledge. Control of plasma glucose requires alteration of insulin doses as pregnancy proceeds. Mothers with retinal, renal or cardiac problems will need special care. The medical problems which develop, and the management of blood glucose during labour and delivery, mean that the diabetes team must be very adjacent to the obstetric service, and a centralised approach offers many advantages. The postpartum state, and the long-term outcome for both mother and baby, remain both an interest and a responsibility for the obstetric physician.