The Emory Islet Transplant Program will enroll ten patients, ages 18 to 65, in the study. Each of the ten patients will receive at least 2 islet transplants from 2 different organ donors. A third transplant may be required based on the patient's insulin requirements after the 1st two transplants. Each patient will be placed on immunosuppressive drugs to prevent the body from rejecting or destroying the transplanted islets. Each patient will have his/her blood sugar levels and insulin requirements monitored very closely after each transplant. The patients will also have various tests to determine if their diabetic complications improve, remain the same, or become worse. The patients will be asked to record any episodes of hypoglycemia or low blood sugars while participating in this study. Emory will examine whether or not there is a decrease in how often the episodes occur. Patients will also undergo regular eye exams to document retinal changes or improvements that may occur after transplant. At this time it is not known whether islet transplantation slows or stops the progression of common diabetic complications. More experience and research is needed before this can be determined. One focus of our research will be to study diabetic complications in patients who receive islet transplants.