Continuous subcutaneous insulin infusion (CSII) was initiated in a young female adolescent with severe insulin resistance, decreased growth velocity, and poor metabolic control. The patient's insulin dose had been 3 u/kg/day, and it was hypothesized that her insulin requirements would be much less when only regular insulin was used. Because of the potential risk of severe hypoglycemia from giving regular insulin in amounts equivalent to her injection total daily dose as a constant subcutaneous infusion, the patient was hospitalized to begin pump therapy. Hourly glucose levels were collected for 24 hours to determine insulin requirements with this therapy. The patient subsequently required a significantly reduced dose of insulin (1.2 u/kg/day) with CSII, and her growth velocity improved. Metabolic control based on glycosylated hemoglobin levels also improved. Insulin pump treatment proved to be a viable solution for this young adolescent who required large doses of insulin to maintain reasonable control. Challenges of using this type of therapy in young patients are discussed.