Botulinum toxin injection is a well tolerated, safe and effective procedure in the treatment of focal spasticity. Evidence of its benefit is gradually accumulating from randomized controlled trials. In this article, the evidence supporting the use of Botulinum toxin injections in spasticity has been rewieved; then the technical issues including the selection of the patient suitable for treatment, the appropriate dosage, selection of the target muscles, injection technique, aftercare and the necessary follow-up procedures have been documented.