Current debate about the use of insulin infusion pumps in the treatment of diabetes mellitus is partly attributable to a lack of available data about the long-term course of patients who use pumps. We evaluated the course of our first 20 patients treated with insulin infusion pumps. Two or more years after the inception of therapy, only half of these patients were still using the insulin infusion pump. Psychosocial stresses, which affected glycemic control, were identified retrospectively in a majority of patients, but were not appreciated when pump therapy was initiated, despite our best attempts to do so. Mean hemoglobin A1 levels decreased significantly for the entire group and for the subgroup that did not discontinue pump therapy. These results suggest that insulin pump programs must have the resources to provide appropriate support for all candidates, including unsuitable candidates, who present for treatment with insulin infusion pumps.