Type I diabetes is one of the big challenges in medicine of the 21st century, being a chronic disease with a high incidence and long term complications. Intensive insulin treatment can reduce these complications but harbors the risk of hypoglycemic events impacting on the quality of life of patients. Pancreas and islet of Langerhans transplantation are interesting alternatives to restore physiologic glucose metabolism. One could think that there might be some competition between these two treatments, but donor and recipient selection criteria are different and these two methods are therefore complementary. Here we discuss the adequate donor selection and the different settings of beta cell replacement therapy for type I diabetes, their risks and their benefit.