The purpose of this audit is to evaluate practice variation at the emergency department in comparison with best practice for brain imaging in children presenting with headache. The American College of Radiology published a guideline on Appropriateness Criteria stratifying low risk (usually not appropriate) and high risk (usually appropriate) groups based on signs and symptoms. Brain imaging here is defined as computed tomography (CT) or magnetic resonance imaging (MRI) scan. This is a retrospective study including 600 patient visits over 1 year from Feb 1 2014 – Jan 30 2015 from emergency department records at the Stollery Children’s Hospital, Edmonton, Canada. Most paediatric patients that presented to the emergency department with headache did not receive neuroimaging. CT scans were done more often than recommended and not all patients who met criteria always received brain imaging. There is some variability in the application of the American College of Radiology’s Appropriateness Criteria, although most cases were found to be handled appropriately in this study. The results of this study might be used to inform a clinical prediction rule to better stratify risk as per the Appropriateness Criteria.