Two teenage patients, who had severe psychosocial problems that complicated their diabetes management, were treated for one month (14-year-old girl) and two months (16-year-old boy) by frequent pulses of insulin injected subcutaneously by a portable, programmed pump. Additional pulses were manually adjusted by the patient before eating. Both patients experienced improved sense of well-being, marked reduction in urine volume and in glycosuria, and reduced glycemic excursions and average levels. The boy had accelerated linear growth and a decreas in HbA1 percentage. Despite marked clinical improvement, permitting return to school, the girl was impelled to interrupt pump administration after two weeks. Both patients continue to use the device voluntarily; a smaller unit, however, that doesn't have the conspicuous external controls, would likely be readily acceptable to most young patients.