We report four patients with tics since childhood who presented with typical Parkinson's disease (PD). No alteration in tics occurred before or during the development of symptoms. L-Dopa/carbidopa therapy in three patients improved parkinsonism without worsening tics over 3 months to 11 years of follow-up. Our experience fails to support hypotheses exclusively emphasizing overactivity of dopaminergic function underlying tics that would predict that PD would reduce and L-dopa exacerbate tics. This emphasizes the role of other neurotransmitter systems in the pathophysiology of tics.