Abstract Diabetes has long been recognized as a risk factor for a variety of medical conditions that predispose patients to hospitalization, and it is associated with poor outcomes. Patients with diabetes are likely to be admitted for coronary artery disease, cerebrovascular or peripheral vascular disease, nephropathy, infection, or surgery. Hyperglycemia occurs frequently in hospitalized patients. Studies suggest that hyperglycemia in the hospital setting is an indicator of poor clinical outcomes in critical and noncritical patients. A growing body of clinical evidence indicates that effective glucose control in a hospital setting may improve short-term and long-term morbidity and mortality in patients with diabetes and hyperglycemia.