During a 10-year period, 101 children with Type 1 (insulin-dependent) diabetes mellitus were admitted to the Department of Paediatrics of the University Hospital in Khartoum, Sudan. The age distribution of the patients showed a steady increase from age one to ten years followed by a sharper increase around puberty. A higher number of cases were diagnosed during the cooler compared to the warmer months of the year (p less than 0.05). Family history of Type 1 diabetes was reported in 14.9% of patients. Diabetic ketoacidosis was a presenting symptom in 82 patients (81.2%) and 93 patients (92.1%) have had at least two documented episodes of ketoacidosis during the follow-up period. Almost all patients were treated with bovine insulin given as a single dose per day. An initial remission period was not observed in any of the patients. Four years after diagnosis, the average daily dose of insulin used by the patients was greater than 2.0 U/kg body weight and the mean HbA1C was 13.4% (reference value 5.3-6.7%). Seventeen patients (16.8%) were known to have died during 399 person-years of observation resulting in a mortality rate of 42.6 per 1000 person-years of follow-up. Another 29 patients (28.7%) for no apparent reason did not attend a follow-up examination after discharge from hospital. Some of these patients might have died in other hospitals or at home. The study emphasizes the need for urgent measures to increase public awareness of diabetes and to improve methods of case-finding and management of diabetic patients.