This paper is a narrative review of the literature regarding in-hospital glucose regulation. Due to the increasing prevalence of diabetes in modern day medicine, proper management has never been more important. Acutely ill patients are at increased risk for developing hyperglycemia regardless of whether or not they have a pre-admission diagnosis of diabetes. The practice of maintaining tight glycemic control has been debated in the literature as it can be associated with an iatrogenic risk of hypoglycemia. However, there is a body of evidence that good glycemic control is associated with better outcomes. Currently, there is a consensus that blood glucose in hospitalized patients should be maintained below 10 mmol/L - an aim which might be individualized according to specific patient's variables and concurrent treatment plans. Insulin is recognized by most institutions as the treatment of choice in critically and non-critically ill patients in the hospital setting and is associated with better health outcomes compared to other modalities which are currently not recommended. However, in non-critically ill patients and those admitted for minor surgery their former treatment might be continued if blood glucose control is good. Stress hyperglycemia is fairly common in acutely ill patients and is associated with later development of new-onset diabetes thus reinforcing the value of effective communication and proper follow up in such patients.