A study was carried out to determine the clinical effectiveness of intramuscular botulinum toxin type A (BTX) in the treatment of spasticity or dystonia in 58 consecutive children with cerebral palsy (CP). The effectiveness of the treatment was determined by the reduction of spasticity and global parental perception scale. The mean age of treatment was six years and the most frequent aim of treatment (91.1%) was functional improvement. The median reduction of spasticity as measured by modified Ashworth scale was 1. The short term outcome was graded as excellent or good by 44.6% and satisfactory by 38.4% of parents. Patients with dyskinetic Cerebral Palsy had the best response. Adverse effects were minimal. BTX treatment is modestly effective in the majority of our patients with spastic and dyskinetic cerebral palsy.