Despite published evidence supporting glycemic control in critically ill patients, achieving euglycemia remains a problem in the intensive care units (ICUs) of many institutions. Clinicians seeking to implement the findings of published evidence in their practice face many potential barriers that make euglycemia difficult to achieve in patients in the ICU. Developing a comprehensive understanding of the many barriers to ICU glucose control can aide clinicians in attempting to change practice and improve patient outcomes. Barriers to ICU glucose control include the role of different health professionals in glucose management, communication among health care professionals, guidelines, protocols, ICU culture, fear of hypoglycemia, glucose monitoring, education, systems analysis, health care resources, nutritional needs, and drug utilization. By ensuring compliance, changing ICU culture, developing guidelines and protocols, and incorporating a multidisciplinary approach, clinicians can achieve glycemic control in the critically ill population and improve patient outcomes.