Tourette's syndrome is described as a neuropsychiatric disorder of childhood, reflecting the interaction between genetic, neurophysiological and environmental factors, which change in their expression during the course of development. The recent research directed on the neurochemical aspects of the syndrome is reviewed. Although no specific biochemical marker are found sofar, there is some evidente that noradrenergic, dopaminergic, cholinergic and serotonergic mechanisms are playing a role in the pathophysiology of this disease.