This is a particularly exciting time in the field of pancreatic islet growth, development, and survival. The recent publication of a study demonstrating that human pancreatic islet transplantation is both technically and immunologically feasible has highlighted the need for large supplies of pancreatic islets or pancreatic β cells for larger-scale islet transplantation in patients with diabetes. This, together with a rapid expansion in the past several years of the understanding of mechanisms of islet growth, development, and survival, has accelerated and invigorated efforts to therapeutically harness the cellular mechanisms responsible for pancreatic β-cell proliferation, survival, and development and to take advantage of this new knowledge to enhance the availability, survival, and function of pancreatic β cells in human islet transplantation for diabetes mellitus. Here, we briefly review the confluence of events that have provided optimism and energy to the islet transplant field, and we focus on pepti...