Potential study participants will be recruited from the Endocrinology and Transplant clinics at the Ohio State University, and community physician referrals. Those who are potentially eligible will undergo a screening evaluation after review of the medical records. If the subject remains eligible, he/she will be enrolled in the islet transplant study and will be placed on a waiting list for an islet transplant. Once a transplant becomes available, the subject will be admitted to the hospital to undergo the transplant procedure. Frequent follow-up visits in the transplant clinic will occur throughout the following year after the transplant. Subjects will be closely monitored for adverse events and insulin requirements. If the subject does not achieve insulin independence, he/she may be eligible for a subsequent transplant.