These guidelines summarize the current views of the European Association of Nuclear Medicine Neuroimaging Committee (ENC). The aim of the guidelines is to assist nuclear medicine practitioners when making recommendations, performing, interpreting, and reporting the results of clinical dopamine transporter (DAT) single photon emission computed tomography (SPECT) studies using I-123-labelled radiopharmaceuticals. The aim is to achieve a high-quality standard of DAT SPECT imaging, which will increase the diagnostic impact of this technique in neurological practice. The present document is an update of the 2002 guidelines  and has been guided by the views of various national societies: the Task Group Neuro-Nuclear-Medicine of the German Society of Nuclear Medicine , a consensus statement of the imaging centres included in the "Kompetenznetz-Parkinson" sponsored by the German Federal Ministry of Education, and the Task Group of Neuro-Nuclear-Medicine of the French Society of Nuclear Medicine . The guidelines reflect the individual experience of experts in European countries. The guidelines are intended to present information specifically adapted to European practice. The information provided should be taken in the context of local conditions and regulations.