In every paediatric emergency department and children’s assessment unit, the child presenting with a fever while undergoing chemotherapy, is a regular event. These children can look quite well but missing sepsis will be a disaster. Some guidelines will insist in the starting of the antibiotic before even knowing the white cell count result. Measuring and defining fever, agreeing on how to take a temperature and what thermometer to use, are critical when interpreting a child’s temperature. Many of the oncological clinical guidelines on the management of children with fever and neutropenia use a wide range of temperature …