We describe a 13-year-old boy with Tourette's syndrome (TS) manifested chiefly by severe coprolalia, obsessive compulsive disorder, and attention deficit hyperactivity disorder. He was treated with unilateral injections of botulinum toxin to the vocal cord and experienced marked improvement in coprolalia as well as marked reduction in the premonitory urges associated with the vocal tics and coprolalia. As a result of the improvement, the patient was able to attend school and church and was able to socialize. Botulinum toxin may interfere with a sensory reflex arc required to perpetuate tics and coprolalia in TS, possibly by reducing local build-up of tension or muscle contraction in affected areas.