A knowledge of the doses that patients receive is important to optimize radiation protection in diagnostic radiology. This chapter covers the methodology involved in assessment and management of patient dose for radiography and fluoroscopy. The dose quantities are described and ones to use for different applications are discussed. The instruments and measurement techniques used are described, including passive techniques such as TLD and radiochromic film. The need to consider scattering of X-rays from surfaces is explained. Factors to be taken into account include whether the assessment is for practical evaluation of technique or to provide an indication of risk. The appropriate dose to assess could be that to the whole body, the skin surface, or a particular organ such as the breast in mammography. These factors all feed into the patient dose audit process, which is explained together with the setting of diagnostic references levels to aid optimization.