Twelve dogs had transplantation of almost the entire small intestine in the orthotopic location; immunosuppression was with cyclosporine and prednisone. Half the dogs had survival of at least one month, and a third lived for at least four months. Two of the animals are still living after 550 and 555 days. Maintenance of nutrition, and absorption of D-xylose and fat were better than in control animals with an iatrogenic short gut syndrome, but distinctly worse than that of normal dogs.