Nineteen combined renal and segmental pancreatic transplantations with enteric exocrine diversion were performed between May 1984 and September 1985. The one year actuarial patient survival rate and pancreatic graft survival rate were 86 and 66 per cent, respectively. Thirteen pancreatic grafts are presently functioning (two to seven months) and all of the recipients are insulin-free. Although graft cold ischemia time was kept low (a mean of 4.6 hours), a moderate graft pancreatitis developed with a peak serum amylase level of 16.8 +/- 2.2 microkatal per liter. Analysis of the fluid drained through an abdominal drain tube placed at the graft site revealed an amylase activity of 280 +/- 110 microkatal per liter on the first postoperative day and rapidly decreasing to a mean of 15 +/- 5 microkatal per liter on day 6. A pancreatic duct catheter was used to divert the exocrine juice to the exterior during the first few postoperative weeks thereby promoting healing of the pancreaticoenteric anastomosis. The volume of pancreatic juice from the ductal catheter was quite low in the first postoperative days but then rose to reach a plateau level of 500 to 600 milliliters. The amylase activity and the lipase concentration in the pancreatic juice was very high (9,100 +/- 2,450 microkatal per liter and 11.1 +/- 4.4 grams per liter, respectively) during the first postoperative day but then gradually decreased to reach a steady level after four to seven days. Intravenous administration of secretin induced a sixfold increase in the flow of pancreatic juice. An intravenous infusion of somatostatin significantly reduced the flow of pancreatic juice and the amylase activity and lipase concentration in the juice but did not abolish the secretin induced increase in pancreatic secretion.