Empyema is a common cause for hospital admission in children. For years, clinicians have relied on chest X-rays to aid diagnosis and monitor treatment. New imaging techniques, particularly ultrasound, have helped in planning the management of children with empyema. Other cross-sectional radiological investigations are useful in a small proportion of children with complicated disease. The mainstays of imaging in the vast majority of children with empyema are chest radiography and ultrasound.