The treatment of adult and pediatric patients suffering from movement disorders with elevated muscle tone includes the application of focally denervating botulinum toxins. Dystonic movement disorders in adult patients have been treated successfully using botulinum toxin type B (NeuroBloc). Thus far, there has been no systematic treatment of children with botulinum toxin type B. This study reports on the treatment of 29 children with spastic or dystonic movement disorders using botulinum toxin type B in an open-label pilot study. Sixty-two treatment sessions were performed. In 33 of these sessions, the therapy goal that had been defined before intervention was attained or surpassed. Seventeen nonresponders to botulinum toxin type A were also included in the treatment, 11 of whom attained the therapy goal. Side effects were observed in 24% of all treatments, dry mouth being the most frequent (10%), in some cases having a desirable clinical effect. With this preliminary data as a basis, we recommend a maximum dose for children of 400 U botulinum toxin type B per kg body weight, which should not exceed a total of 10,000 U botulinum toxin type B.