Hospital acquired infections are a major cause of morbidity and mortality and markedly increased health care costs. Critically ill patients who require management in an Intensive Care Unit are particularly susceptible to these infections which are associated with a very high mortality. Selective decontamination of the digestive tract (SDD) may reduce these infections and improve mortality but it has not been widely adopted into practice. We aim to 1. Clarify reasons why clinicians have avoided implementing SDD into clinical practice despite the current best-evidence 2. Describe barriers to SDD implementation and 3. Identify what further evidence is required before full scale clinical implementation would be considered appropriate and feasible.