Successful islet transplantation would result in larger number of insulin-independent recipients compared with whole organ pancreas transplantation, both because of a larger donor pool and a larger transplant candidate pool. In addition to the usual screening done for solid organ transplant, weight and insulin requirement are important factors in considering candidacy for islet transplantation. Islet donors undergo the same screening as solid organ donors, although acceptable age and BMI for islets are much higher than for whole pancreas. Islets are quantified by packed tissue volume (5-10ml per infusion) and by islet equivalent (IE). Percutaneous infusion requires only local anesthesia and is performed by interventional radiology via transhepatic catheterization of the portal venous system. Agents such as exenatide/Byetta aims to improve the function of existing islets. Besides developing new pharmaceuticals and bioagents, tolerance induction and encapsulation technology are also possible methods to protect allo-islets from the recipient immune system.