Hyperglycemia, hypoglycemia, and glycemic variability are all independently associated with morbidity and mortality of critically ill patients. A strategy aiming at normoglycemia (so-called tight glycemic control) could improve outcomes of critically ill patients, but results from randomized controlled trials of tight glycemic control are conflicting. Strict glycemic control is associated with an increased risk of hypoglycemia, which could offset the benefit of this intervention. Notably, the risk of hypoglycemia is not necessarily removed with less tight glucose control regimens. The best targets of blood glucose control in critically ill patients, therefore, remain a matter of debate. It should be realized that blood glucose control is a complex intervention, consisting of many critical aspects that have the potential to affect its efficacy and safety. Efficacy, and in particular safety, of blood glucose control could still improve. First, glucose algorithms could overcome the lack of knowledge and skills of nursing staff when they are less experienced in safe and efficient blood glucose control. Several computerized glucose control algorithms have been developed over recent years, but they all need clinical validation. Also, the workload induced by such algorithms should be evaluated. Second, continuous blood glucose monitoring has the potential to improve safety and efficacy. Until recently, blood glucose levels were monitored manually using point-of-care devices with significant inaccuracies. Various continuous monitoring systems have been developed, but studies testing their accuracies and usefulness in an intensive care unit setting are highly needed.