Beta cell replacement therapy is currently the only treatment method that allows restoration of physiological endogenous insulin secretion in the amounts corresponding to the current body requirements. Beta cell replacement options available for highly selected patients with brittle type 1 diabetes include solid-organ pancreas and islet transplantation. Beta cell replacement therapy may be offered to patients with both good kidney function and renal failure. In progressive renal failure, beta cell transplantation may be performed simultaneously with kidney transplantation or afterwards. Islet autotransplantation is offered to patients submitted to total pancreatectomy. In patients with brittle type 1 diabetes who continue to experience life threatening severe hypoglycaemia episodes despite optimized insulin therapy, beta cell replacement helps improve hypoglycaemia awareness, thus reducing the risk of severe hypoglycaemia episodes, facilitates blood glucose control with normalization of haemoglobin A 1c (HbA 1c) level, and reduces microvascular disease progression. In patients undergoing total pancreatectomy, infusion of the patient's own islets isolated from the removed pancreas prevents blood glucose level excursions and reduces the risk of surgically-induced diabetes. In this article, we review the current indications and contraindications to beta cell replacement, expected benefits, and possible complications of beta cell transplantation.