Ambulatory EEG (A-EEG) allows long-term EEG monitoring under dynamic conditions: patients, therefore, are not confined to a small room, but they are free to perform their normal daily activities. This method is fairly comfortable for the patient and relatively inexpensive as it does not require hospitalisation. The usefulness of an A-EEG includes a wide spectrum of advantages, the detection of epileptiform activity not evidenced during standard EEG being one of the main ones. Other important A-EEG advantages is its utility in the differential diagnosis between epileptic and non-epileptic manifestations, in the confirmation of drug efficacy or in the detection of epileptiform activity during sleep