Primary cervical dystonia (CD) affects about 20-40/100.000 population. The disease is chronic and life-long. The therapy of choice are local intramuscular Botulinum Toxin injections given every three months. Oral medication such as anticholinergics or dopamine depleting drugs are usually of limited efficacy or their use is limited by intolerable side-effects. About 5-10% of CD patients develop neutralizing antibodies against Botulinum Toxin. Two previous controlled multicenter trials have shown the efficacy and safety of bilateral pallidal stimulation in patients with primary segmental and generalized dystonia (one study was performed by our group).