In this paper the use of PET for determining the patterns of disruption of both regional cerebral metabolism, and the pre- and post-synaptic dopaminergic systems, associated with movement disorders is reviewed. That the various akinetic-rigid syndromes result in distinctive PET findings is shown, making functional imaging valuable in their differential diagnosis. PET may also be useful for detecting the presence of sub-clinical disease in Huntington's disease and other inherited movement disorders.