The seemingly sudden advent of regenerative medicine as a recognized research and clinical field has allowed us to envisage a number of potential treatments for diseases thus far considered incurable. Nowadays, it is not uncommon to discuss prospective stem cell therapies for the recovery of motor function following spinal cord injury, the replacement of dopaminergic neurons in Parkinson's disease or even the generation of patient-matched gametes in some cases of infertility, just to mention a few examples. While the promise of this emerging field is substantive enough to justify the pursuit of regeneration strategies for these and other conditions, the truth is that, to date, there is none for most of them. Whether or not we will come up with any such therapies in the future is not known. Diabetes is one clear exception. For more than two decades, islet transplantation has shown its clinical efficacy, with many patients either completely off-insulin or with a much improved metabolic control years after the procedure. Based on this palpable proof of principle, we can safely assume that, if stem cells could be induced to differentiate into insulin-secreting beta cells, the benefits of islet transplantation could be made available to millions of patients. Here we review the clinical perspectives of the regeneration of the endocrine function of the pancreas, an ongoing effort that is building upon, and going beyond, the success of islet transplantation.