Background: Upper limb function is essential for activities of daily living impacting on quality of life in children with cerebral palsy (CP). In preschool children, dysfunctional upper extremity manipulation not only leads to disability but may further delay global development and substantially increase career burden. Even modest functional improvement could have tremendous long-term benefit in activities of daily living and significantly reduce career burden. Hypertonia is the main symptom causing motor dysfunction in CP. Intramuscular Botulinum toxin injection is one way of treatment. In spite of anecdotal evidence suggesting that early intervention can lead to better outcomes, Israeli physicians are unable to prescribe this treatment for the upper extremities due to limited health insurance coverage. A paucity research evidence is often cited as the reason for limiting the insurance coverage, in particular to the upper limb. We therefore propose to study the effects of Botox® in treating children with CP.