Diabetes is now one of the most prevalent diseases in the world. Over the next twenty years, the number of affected individuals could reach 693 million. Diabetes is a group of chronic carbohydrate metabolism disorders responsible for increased blood glucose levels. It has several effects on the human body, and over the years can even become disabling, greatly impacting the patient’s quality of life. The most common therapy is based on daily and chronic administration of exogenous insulin, but this is associated with a series of dangerous and potentially fatal complications. Unsurprisingly therefore, over time, studies have explored various alternatives for the treatment of diabetes, not involving the use of insulin, primarily transplantation of the whole pancreas and of the islets of Langerhans. However, neither of these solutions can be applied on a large scale, mainly due to the lack of donors. In recent years, a viable alternative to insulin and to transplantation has emerged through exploration of the use of pluripotent stem cells and their properties. In this review we analyze the state of the art in this field, and the advantages and disadvantages of cell therapies used for reconstruction of the functional unit of the pancreas, the islets of Langerhans.