In recent decades significant advances in the understanding of neurobiological substrates of Tourette's Syndrome (TS) have led to the formulation of hypotheses regarding the ways in which the most salient features of the syndrome may occur. Pathophysiology of TS involves multiple intertwined neurobiological issues in different areas of the Central Nervous System. This review considers neuroimaging studies (MRI, PET, SPECT) in patients with TS. Neurochemical neurophysiological and electrophysiological studies are also reviewed. The role of the neuroendocrine and neuroimmunologic mechanism on pathogenesis of the disease is discussed. Advances in diagnostic techniques (fMRI, mMRI, PET, SPECT) and in neurophysiological research on neurotransmitter systems will allow us to better understand the pathophysiology of TS and to use more specific treatments.