Early Warning Scores (EWS) have become increasingly used by hospitals throughout the world to prevent unexpected admission to intensive care or even death in their inpatient population. It is well known that signs of deterioration are present well before collapse and by a combination of systems, EWS enable healthcare professionals to intervene at an appropriate time. A number of national bodies and regulators in the UK have required the use of Early Warning Scores in locations where children are inpatients. This article attempts to describe the background to their development, identify common problems and provide information for units interested in introducing an EWS into their department.