A total of 1,859 intestinal transplants was reported to UNOS during the past 20 years (1,822 deceased, and 37 living donors). Forty-three US transplant centers reported at least one intestinal transplant, among them, Jackson Memorial Hospital, Nebraska Medical Center and University of Pittsburgh Medical Center were the 3 largest centers, each performing more than 300 cases. The University of Illinois Medical Center performed the most (N = 24) living donor intestinal transplants. The one-, five-, and ten-year graft survival rates of all recipients are 71%, 45%, and 32%. The longest surviving adult intestine transplant is 19 years posttransplant and the longest surviving pediatric transplant is 18 yrs. Both were simultaneous intestine and liver transplants from deceased donors. The first living-donor intestine transplant was reported to UNOS in 1995. The patient received an intestine-alone transplant which functioned for 501 days. The longest surviving living donor intestine transplant is still functioning after 11 years. Among transplants that included the intestine, 37% were intestine-alone transplants, 30% included intestine+liver+pancreas, and 24% were intestine+liver. One-, 5-, and 10-year graft survival rates of intestine-alone recipients were 80%, 44% and 26%; while those for Intestine+liver and intestine+liver+pancreas, were, 62%, 45%, 36%, and 69%, 48%, 33%, respectively. HLA mismatches seemed to have no effect on graft survival for primary intestinal graft recipients, but the most poorly matched (5-6-HLA antigen mismatches) regraft recipients had notably lower graft survival rates. Patients who received ABO blood type compatible intestinal grafts from an "O" donor had a significantly lower graft survival than AB recipients of an A or B donor or those who received ABO identical transplants. Only 4 ABO incompatible intestinal transplants have been reported and all of them have failed. The first ABO incompatible transplant in the US was performed in 1990 and the graft survived for 7 days. The longest survival of an ABO incompatible transplant was 3.5 years. Ischemic time of intestine, patient's and recipient's CMV status had no effect on graft survival. Patients with a history of rejection episodes posttransplant or who had been previously transplanted had significantly lower graft survival rates. Acute rejection, chronic rejection and infection were among the major causes of graft failure. Infection, multiple organ system failure and graft rejection were the major causes of patient death. Induction therapy was used for 67% of all intestine recipients, which is lower than for kidney (83%) but higher than for liver recipients (59%). Thymoglobulin remained the most commonly used antibody since its introduction into intestine transplantation in 1999. In recent years, more patients received Zenapax/Simulect (anti-IL-2 receptor), Campath (anti-CD52) and Rituximab (anti-CD20). These antibodies were usually used in combination with other immunosuppressants. Patients receiving steroids and Campath induction therapy had higher graft and patient survival than other protocols. Prograft, steroids, Cellcept and Rapamycin were the 4 major immunosuppressants used in maintenance therapy. Prograft and steroids have been used more than 20 years since the initiation of the UNOS intestine database in 1990. Among all maintenance immunosuppression protocols, Prograft+steroids (43%), Prograft-alone (14%), Prograft+steroids+ Cellcept (11%), and Prograft+steroids+Rapamycin (6%) are the top 4 major protocols. Patients on Prograft+steroids+Rapamycin had the highest graft and patient survival rates, while those on steroids alone had the lowest.