The use of positron emission tomography co-registered with computed tomography (PET-CT) in adult oncology, neurology and cardiology is well established. The most common tracer used in clinical PET-CT is 18Fluorine fluorodeoxyglucose (FDG). However, experience with PET-CT in the field of paediatric imaging is limited. In the face of limited published data and experience, this report was compiled by individuals with experience in scanning children with PET-CT in the UK and paediatricians involved in clinical management of the type of conditions for which PET-CT is likely to be used. It represents a consensus reached between the authors of what is desirable ‘best’ practice.