Modern imaging techniques that visualize disease-specific organ neurotransmitter or protein receptor sites are increasingly able to define pathological processes on a molecular level. One of those imaging modalities, positron emission tomography (PET), for the assessment of brain neuroreceptor binding has revolutionized the in vivo assessment of biologic markers that may be related to human behavior. Such studies may help identify chemical targets that may be directly related to psychiatric pathology and, thus, opportunities for pharmacological intervention. In this review, we describe results from PET studies in eating disorders (EDs). Eating disorders are frequently debilitating illnesses that are quite homogeneous in their presentation. Those studies that identified particular serotonin and dopamine receptor alterations can distinguish recovered ED subjects from controls as well as ED subgroups. Furthermore, correlations of receptor binding with behavioral constructs, such as harm avoidance or novelty seeking, could be found. These recognized receptors may now help us to move away from rather nonspecific treatment approaches in psychiatric research and clinic to the possibility of more syndrome- and symptom-specific treatment approaches.