[en] Medical x-ray examinations contribute greatly to the population dose from man-made radiation sources. There is a need to control this dose and therefore to optimise the design and use of x-ray imaging systems. A key stage in this process is the standardisation of the procedures for dose measurement in the clinic. The Dosimetry and Medical Radiation Physics Section of the IAEA has a number of activities to further advance the standards for x-ray diagnostics. One of these activities is the coordination of a working group to develop a code of practice, which will facilitate the IAEA calibration activities, TLD intercomparisons and audits, educational activities, and technical assistance to Member States. The code of practice will aid in the standardisation of various dosimetric techniques in x-ray diagnostic radiology. The CoP working group has had an initial meeting to review the current status of dosimetry for conventional radiology, fluoroscopy, mammography, computed tomography and dental radiology. The CoP will include the establishment of standards and calibrations at the SSDLs, phantom and patient measurements and procedures for dosimetry in the clinic. (author)