Insulin: Deficiency, Excess and Resistance in Human Disease provides an overview of the role of insulin in the pathogenesis of prevalent non-communicable diseases such as obesity, type 2 diabetes, cardiovascular disease, and cancer, along with a comprehensive review of insulin replacement therapies and novel cardioprotective and insulin-sensitizing drugs. Notable advances in precision diagnosis and therapy for single gene subtypes of diabetes in recent years are also discussed. The discovery of insulin and its lifesaving introduction into clinical practice is one of the most celebrated accomplishments of medical science. However, despite decades of progress and major technical advances, the goal of providing insulin replacement therapy that truly mimics normal physiology remains elusive.