[en] Maladministration has been defined as the mistaken administration of a radiopharmaceutical to a patient. Examples include the administration of the wrong radiopharmaceutical or the wrong activity to the correct patient or the administration of the correct radiopharmaceutical to the wrong patient. Although maladministrations are rare, lessons can be learnt from the incidents that do occur. Medical maladministrations and other radiation incidents are discussed by members of the NSW Hospital and University Radiation Safety Officers Group (HURSOG) at their bi-monthly meetings. During the three years of 1997-1999 fourteen incidents of maladministrations in nuclear medicine were reported. Analysis of these reports indicated that eight (57 %) were due to the wrong radiopharmaceutical having been administered. This usually occurred because the technologist had selected the wrong lyophilised agent when the radiopharmaceutical was being prepared, or selected the wrong vial of the reconstituted agent. For example, in one instance a vial of MAG3 was reconstituted instead of a vial of HMPAO. These mistakes occurred even though the vials were clearly labelled and sometimes had different coloured labels. Of the remaining 6 cases, two involved the wrong activity being administered due to a mis-read dose calibrator, two involved the wrong procedure being performed following a breakdown in communication and the final two incidents resulted in the wrong patient being administered the radiopharmaceutical. In order to minimise the possibility of recurrence of these incidents the NSW Radiation Advisory Council asked the NSW Branch of the Australian and New Zealand Society of Nuclear Medicine and HURSOG to jointly convene a Working Party to prepare Guidelines for the administration of radiopharmaceuticals. The Guidelines specify: 1. the procedure for the validation of the requested investigation on the request form 2. who should reconstitute, dispense and administer radiopharmaceuticals. 3. how the identity of patients should be confirmed 4. how the pregnancy status of female patients should be confirmed 5. the recommended checking procedures It is hoped that the adoption of these Guidelines will result in a reduction of the incidence of maladministrations of radiopharmaceuticals. Copyright (2002) Australasian Radiation Protection Society Inc