Type 1 diabetes are intrinsically unstable conditions because of the loss of both insulin secretion and glucose sensing. Guidelines to treat type 1 diabetes have become stricter since the Diabetes Control and Complications Trial (DCCT) results demonstrated the close relationship between microangiopathy and HbA1c levels, whereas the deleterious role of glucose variability on macroangiopathy has been more recently suspected. Therapeutic strategies first require the treatment of underlying organic causes of the brittleness whenever possible and, secondly, the optimization of insulin therapy using analogues, multiple injections and consideration of continuous subcutaneous insulin infusion. Alternative approaches may still be needed for the most severely affected patients, including islet transplantation. We propose islet after kidney transplantation in diabetic patients with end-stage kidney disease ineligible for double kidney-pancreas transplantation (i.e C peptide negative patients over 45 years of age or with severe macroangiopathy) if creatinine blood levels are stable below 20mg/l at least six months after kidney transplantation and steroid discontinuation. Islet transplantation alone is proposed to (1) C peptide negative diabetic patients, (2) aged 18-65 with a duration of diabetes of at least five years, (3) treated with intensive subcutaneous insulin therapy, but unable to obtain a glycated hemoglobin level below 7% without hypoglycemia and / or with brittleness and unpredictable hyper- and hypoglycemia altering quality of life, (4) with normal body weight (< 80 kg) and / or low daily insulin needs (the lower, the better), (5) with renal function close to normal (creatinine clearance above 60 ml/min with albuminuria lower than 300 mg/24 h), (6) with no desire for pregnancy in women. Currently and until more complete assessment of the 5-year overall benefit-risk ratio, islet transplantation remains a clinical research procedure. As already provided for other types of transplantation, and once recognized as a "routine" procedure, prioritization of enlisted patients for islet transplantation could be aided by the calculation of a score that should be determined by a multidisciplinary team.