The aim of this study was to develop a model for pancreatic transplantation in the primate in order to test a new immunosuppressive drug. Initially, streptozotocin was used to induce insulin-dependent diabetes mellitus, but it was found to be ineffective and associated with a high morbidity. Furthermore, streptozotocin-induced insulin-dependent diabetes mellitus did not always persist, thus invalidating the evaluation of pancreatic graft function. Therefore, total pancreatectomy was introduced and combined with the pancreatic allotransplantation as a single procedure. Enteric diversion of the pancreatic juice was chosen since this avoids exocrine pancreatic insufficiency and facilitates the oral administration of the test drug. Intra-arterial monitoring of blood pressure and blood gases during the operation and avoidance of hypothermia in the animal were found to be the most important factors contributing to a successful outcome from the operative procedure.