Type 1 diabetes is a chronic auto-immune disease. Type 1 diabetes was previously called insulin-dependent diabetes mellitus (IDDM) or juvenile-onset diabetes. Type 1 diabetes develops when the body's immune system destroys pancreatic beta cells, the only cells in the body that make the hormone insulin that regulates blood glucose. To survive, people with type 1 diabetes must have insulin delivered by injection or a pump. Topics discussed in this compilation include genetic and epigenetic studies of type 1 diabetes; blood pressure and diabetes during pregnancy; comparison of diseases-specific quality of life, metabolic control and cardiorespiratory fitness in physically active and inactive youths with type 1 diabetes; stem cells for the treatment of patients with type 1 diabetes; and the causes and potential complications of type 1 diabetes.