In 2013 the Italian Pharmacy Agency (AIFA) approved onabotulinumtoxin A injection to prevent headaches in adult patients with chronic migraine (headaches on at least 15 days per month of which at least 8 days are with migraine) that has not responded to at least three prior pharmacological prophylaxis therapies and whose condition is appropriately managed for medication overuse. In the present paper we report the method of injection of Onabotulinumtoxin A for chronic migraine based on the PREEMPT paradigm as described by Blumenfeld et al. (Headache 50:1406-1418, 2010) adapted to our clinical setting.