This publication draws on an IAEA coordinated research project and provides recommendations specific to the measurement and interpretation of radiation dose to children received as a result of undergoing diagnostic radiological examinations. It complements the work of Dosimetry in Diagnostic Radiology: An International Code of Practice (Technical Reports Series No. 457) and extends this work in methodologies for dosimetry in clinical environments to that required for non-adult patients. It includes dosimetry methodologies for general radiography, fluoroscopy and computed tomography for both phantom and patient measurements. Details are given on dose audit strategies that take into account the size of children and on how the results of such audits can be used to indicate or be related to diagnostic reference levels. The effects of radiation on non-adults are also reviewed, as are the factors involved in the management of paediatric dosage in the clinical setting.